UPDATE: Eventually this message appeared:

The database configuration failed with the following message: This SqlTransaction has completed; it is no longer usable. Please check log file for additional information (can be found in '/App_Data/Logs/UmbracoTraceLog.txt')

And this in the logs:

2014-06-11 14:59:00,969 [6] WARN  Umbraco.Web.UmbracoModule - [Thread 27] Umbraco is not configured

2014-06-11 14:59:34,876 [6] INFO  Umbraco.Core.Persistence.UmbracoDatabase - [Thread 14]    at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)

   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)

   at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error)

   at System.Data.SqlClient.TdsParserStateObject.ReadSniSyncOverAsync()

   at System.Data.SqlClient.TdsParserStateObject.TryReadNetworkPacket()

   at System.Data.SqlClient.TdsParserStateObject.TryPrepareBuffer()

   at System.Data.SqlClient.TdsParserStateObject.TryReadByte(Byte& value)

   at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)

   at System.Data.SqlClient.SqlCommand.RunExecuteNonQueryTds(String methodName, Boolean async, Int32 timeout)

   at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean asyncWrite)

   at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()

   at StackExchange.Profiling.Data.ProfiledDbCommand.ExecuteNonQuery()

   at Umbraco.Core.Persistence.PetaPocoCommandExtensions.<>c__DisplayClass1.<ExecuteNonQueryWithRetry>b__0()

   at Umbraco.Core.Persistence.FaultHandling.RetryPolicy.ExecuteAction[TResult](Func`1 func)

   at Umbraco.Core.Persistence.Database.Execute(String sql, Object[] args)

2014-06-11 14:59:34,970 [6] INFO  Umbraco.Core.DatabaseContext - [Thread 14] Database configuration failed with the following error and stack trace: This SqlTransaction has completed; it is no longer usable.

   at System.Data.SqlClient.SqlTransaction.ZombieCheck()

   at System.Data.SqlClient.SqlTransaction.Rollback()

   at Umbraco.Core.Persistence.Database.CleanupTransaction()

   at Umbraco.Core.Services.MediaService.RebuildXmlStructures(Int32[] contentTypeIds)

   at Umbraco.Core.Events.TypedEventHandler`2.Invoke(TSender sender, TEventArgs e)

   at Umbraco.Core.Persistence.Migrations.MigrationRunner.Execute(Database database, DatabaseProviders databaseProvider, Boolean isUpgrade)

   at Umbraco.Core.DatabaseContext.UpgradeSchemaAndData()

2014-06-11 14:59:35,001 [6] INFO  Umbraco.Core.DatabaseContext - [Thread 14] The database schema validation produced the following summary: 

The following tables were found in the database, but are not in the current schema:

UFFieldsets,umbracoUserGroup,umbracoUser2userGroup,xxx,Mailer,sysdiagrams,UCUserSettings,umbracoapp_temp,umbracoStylesheetProperty,CMSImportState,CMSImportScheduledTask,CMSImportRelation,CMSImportMediaRelation,CMSImportScheduledItems,CMSImportCustomRelation,umbracoStatSession,StandardValues,UFWorkflowsToForms,UFSettings,cmsContentVersionTemp,UFPrevalueSources,UFUserSecurity,UFDataSources,UFFormStates,UFFieldConditions,UFPrevalueSourceSettings,umbracoContentData,umbracoContent,UFFieldConditionRules,UFDataSourceMappings,UFForms,infocaster301_trash,UFWorkflowExecutionStates,UFWorkflows,cmsContentTypes,umbracoContentAll,UFRecordsXml,LookWhosEditingNow,UFRecords,icUrlTracker,UFUserFormSecurity,UFPages,UFRecordFields,UFFields,umbracoStatEntry,UFFieldSettings,umbracoStylesheet,UFPrevalues,UFRecordDataString,UFRecordDataLongString,UFRecordDataInteger,UFRecordDataDateTime,UFRecordDataBit,MediaProtectLog

 

The following columns were found in the database, but are not in the current schema:

UFFieldsets,Id,UFFieldsets,Page,UFFieldsets,SortOrder,UFFieldsets,Caption,umbracoUserGroup,id,umbracoUserGroup,userGroupName,umbracoUser2userGroup,user,umbracoUser2userGroup,userGroup,xxx,Id,xxx,Fieldset,xxx,Fieldtype,xxx,PreValueProvider,xxx,RegEx,xxx,Mandatory,xxx,SortOrder,xxx,Caption,xxx,DataSourceField,xxx,ToolTip,xxx,DefaultValue,xxx,RequiredErrorMessage,xxx,InvalidErrorMessage,Mailer,ID,Mailer,DocumentId,Mailer,MemberId,Mailer,Timestamp,sysdiagrams,name,sysdiagrams,principal_id,sysdiagrams,diagram_id,sysdiagrams,version,sysdiagrams,definition,UCUserSettings,User,UCUserSettings,Key,UCUserSettings,Value,umbracoapp_temp,sortOrder,umbracoapp_temp,appAlias,umbracoapp_temp,appIcon,umbracoapp_temp,appName,umbracoapp_temp,appInitWithTreeAlias,umbracoStylesheetProperty,id,umbracoStylesheetProperty,stylesheetPropertyEditor,umbracoStylesheetProperty,stylesheet,umbracoStylesheetProperty,stylesheetPropertyAlias,umbracoStylesheetProperty,stylesheetPropertyName,umbracoStylesheetProperty,stylesheetPropertyValue,CMSImportState,Id,CMSImportState,UniqueIdentifier,CMSImportState,Name,CMSImportState,ImportType,CMSImportState,ImportState,CMSImportState,Recursive,CMSImportState,Parent,CMSImportScheduledTask,ScheduleId,CMSImportScheduledTask,ScheduleGUID,CMSImportScheduledTask,ImportStateGUID,CMSImportScheduledTask,ScheduledTaskName,CMSImportScheduledTask,NotifyEmailAddress,CMSImportScheduledTask,ExecuteEvery,CMSImportScheduledTask,ExecuteDays,CMSImportScheduledTask,ExecuteHour,CMSImportScheduledTask,ExecuteMinute,CMSImportRelation,Id,CMSImportRelation,UmbracoID,CMSImportRelation,UmbracoParentId,CMSImportRelation,DataSourceKey,CMSImportMediaRelation,Id,CMSImportMediaRelation,UmbracoMediaId,CMSImportMediaRelation,SourceUrl,CMSImportScheduledItems,ScheduledItemId,CMSImportScheduledItems,ScheduleldTaskId,CMSImportScheduledItems,ScheduledOn,CMSImportScheduledItems,ExecutedOn,CMSImportScheduledItems,InProgress,CMSImportCustomRelation,CustomRelationId,CMSImportCustomRelation,UmbracoId,CMSImportCustomRelation,Alias,CMSImportCustomRelation,DataSourceKey,CMSImportCustomRelation,RelatedId,umbracoStatSession,id,umbracoStatSession,MemberId,umbracoStatSession,NewsletterId,umbracoStatSession,ReturningUser,umbracoStatSession,SessionStart,umbracoStatSession,SessionEnd,umbracoStatSession,Language,umbracoStatSession,UserAgent,umbracoStatSession,Browser,umbracoStatSession,BrowserVersion,umbracoStatSession,OperatingSystem,umbracoStatSession,Ip,umbracoStatSession,Referrer,umbracoStatSession,ReferrerKeyword,umbracoStatSession,allowCookies,umbracoStatSession,visitorId,umbracoStatSession,browserType,umbracoStatSession,isHuman,StandardValues,docTypeId,StandardValues,nodeId,UFWorkflowsToForms,Workflow,UFWorkflowsToForms,Form,UFSettings,Id,UFSettings,Key,UFSettings,Value,cmsContentVersionTemp,id,cmsContentVersionTemp,ContentId,cmsContentVersionTemp,VersionId,cmsContentVersionTemp,VersionDate,UFPrevalueSources,Id,UFPrevalueSources,Name,UFPrevalueSources,Type,UFUserSecurity,User,UFUserSecurity,ManageDataSources,UFUserSecurity,ManagePreValueSources,UFUserSecurity,ManageWorkflows,UFUserSecurity,ManageForms,UFDataSources,Id,UFDataSources,Type,UFDataSources,Name,UFFormStates,State,UFFieldConditions,Id,UFFieldConditions,Field,UFFieldConditions,Enabled,UFFieldConditions,ActionType,UFFieldConditions,LogicType,UFPrevalueSourceSettings,PrevalueProvider,UFPrevalueSourceSettings,Key,UFPrevalueSourceSettings,Value,umbracoContentData,versionId,umbracoContentData,alias,umbracoContentData,content,umbracoContent,nodeID,umbracoContent,versionID,umbracoContent,show,umbracoContent,parentID,umbracoContent,nodeUser,umbracoContent,level,umbracoContent,sortOrder,umbracoContent,contentType,umbracoContent,templateNodeId,umbracoContent,documentUser,umbracoContent,language,umbracoContent,createdate,umbracoContent,updateDate,umbracoContent,releasedate,umbracoContent,expiredate,umbracoContent,path,umbracoContent,nodeName,umbracoContent,urlName,umbracoContent,versionUserName,umbracoContent,nodeUserName,umbracoContent,alias,umbracoContent,nodeTypeName,UFFieldConditionRules,Id,UFFieldConditionRules,FieldCondition,UFFieldConditionRules,Field,UFFieldConditionRules,Operator,UFFieldConditionRules,Value,UFDataSourceMappings,DataSource,UFDataSourceMappings,DataSourceField,UFDataSourceMappings,Form,UFDataSourceMappings,PrevalueTable,UFDataSourceMappings,PrevalueKeyField,UFDataSourceMappings,PrevalueValueField,UFDataSourceMappings,DataType,UFDataSourceMappings,DefaultValue,UFForms,Id,UFForms,Name,UFForms,Created,UFForms,ManualApproval,UFForms,GotoPageOnSubmit,UFForms,MessageOnSubmit,UFForms,DataSource,UFForms,ShowValidationSummary,UFForms,HideFieldValidation,UFForms,RequiredErrorMessage,UFForms,InvalidErrorMessage,UFForms,FieldIndicationType,UFForms,Indicator,UFForms,Archived,UFForms,StoreRecordsLocally,UFForms,DisableDefaultStylesheet,UFForms,Entries,UFForms,Views,infocaster301_trash,NodeID,infocaster301_trash,OldUrl,infocaster301_trash,IsCustom,infocaster301_trash,IsRegex,infocaster301_trash,Message,infocaster301_trash,Inserted,UFWorkflowExecutionStates,Workflow,UFWorkflowExecutionStates,State,UFWorkflowExecutionStates,Form,UFWorkflows,Id,UFWorkflows,Name,UFWorkflows,Type,UFWorkflows,SortOrder,UFWorkflows,Active,UFWorkflows,Form,UFWorkflows,ExecutesOn,cmsContentTypes,id,cmsContentTypes,trashed,cmsContentTypes,parentID,cmsContentTypes,nodeUser,cmsContentTypes,level,cmsContentTypes,path,cmsContentTypes,sortOrder,cmsContentTypes,uniqueID,cmsContentTypes,text,cmsContentTypes,nodeObjectType,cmsContentTypes,createDate,cmsContentTypes,pk,cmsContentTypes,nodeId,cmsContentTypes,alias,cmsContentTypes,icon,cmsContentTypes,contentTypeNodeId,cmsContentTypes,templateNodeId,cmsContentTypes,IsDefault,umbracoContentAll,nodeID,umbracoContentAll,versionID,umbracoContentAll,show,umbracoContentAll,parentID,umbracoContentAll,nodeUser,umbracoContentAll,level,umbracoContentAll,sortOrder,umbracoContentAll,contentType,umbracoContentAll,templateNodeId,umbracoContentAll,documentUser,umbracoContentAll,language,umbracoContentAll,createdate,umbracoContentAll,releaseDate,umbracoContentAll,expireDate,umbracoContentAll,updateDate,umbracoContentAll,path,umbracoContentAll,nodeName,umbracoContentAll,urlName,umbracoContentAll,documentUserName,umbracoContentAll,nodeUserName,umbracoContentAll,alias,umbracoContentAll,nodeTypeName,UFRecordsXml,id,UFRecordsXml,Form,UFRecordsXml,xml,UFRecordsXml,created,UFRecordsXml,Page,LookWhosEditingNow,nodeId,LookWhosEditingNow,userId,UFRecords,Id,UFRecords,Form,UFRecords,Created,UFRecords,Updated,UFRecords,State,UFRecords,currentPage,UFRecords,umbracoPageId,UFRecords,IP,UFRecords,MemberKey,icUrlTracker,Id,icUrlTracker,OldUrl,icUrlTracker,OldUrlQueryString,icUrlTracker,OldRegex,icUrlTracker,RedirectRootNodeId,icUrlTracker,RedirectNodeId,icUrlTracker,RedirectUrl,icUrlTracker,RedirectHttpCode,icUrlTracker,RedirectPassThroughQueryString,icUrlTracker,Notes,icUrlTracker,Is404,icUrlTracker,Referrer,icUrlTracker,Inserted,UFUserFormSecurity,User,UFUserFormSecurity,Form,UFUserFormSecurity,HasAccess,UFUserFormSecurity,SecurityType,UFUserFormSecurity,AllowInEditor,UFPages,Id,UFPages,Form,UFPages,SortOrder,UFPages,Caption,UFRecordFields,Key,UFRecordFields,Field,UFRecordFields,Record,UFRecordFields,DataType,UFFields,Id,UFFields,Fieldset,UFFields,Fieldtype,UFFields,PreValueProvider,UFFields,RegEx,UFFields,Mandatory,UFFields,SortOrder,UFFields,Caption,UFFields,DataSourceField,UFFields,ToolTip,UFFields,DefaultValue,UFFields,RequiredErrorMessage,UFFields,InvalidErrorMessage,umbracoStatEntry,SessionId,umbracoStatEntry,EntryTime,umbracoStatEntry,RefNodeId,umbracoStatEntry,NodeId,UFFieldSettings,Field,UFFieldSettings,Key,UFFieldSettings,Value,umbracoStylesheet,nodeId,umbracoStylesheet,filename,umbracoStylesheet,content,UFPrevalues,Id,UFPrevalues,Field,UFPrevalues,Value,UFPrevalues,SortOrder,UFRecordDataString,Key,UFRecordDataString,Value,UFRecordDataLongString,Key,UFRecordDataLongString,Value,UFRecordDataInteger,Key,UFRecordDataInteger,Value,UFRecordDataDateTime,Key,UFRecordDataDateTime,Value,UFRecordDataBit,Key,UFRecordDataBit,Value,MediaProtectLog,LogId,MediaProtectLog,MediaId,MediaProtectLog,Path,MediaProtectLog,Protected,MediaProtectLog,UserName,MediaProtectLog,UserIP,MediaProtectLog,LogDateTime

 

The following constraints (Primary Keys, Foreign Keys and Indexes) were found in the database, but are not in the current schema:

FK_cmsContent_umbracoNode,FK_cmsContentType_umbracoNode,FK_cmsDocument_umbracoNode,FK_cmsPropertyData_umbracoNode,FK_cmsPropertyType_cmsTab,FK_cmsPropertyTypeGroup_cmsPropertyTypeGroup,FK_cmsTask_cmsTaskType,FK_UFDataSourceMappings_UFDataSources,FK_UFDataSourceMappings_UFForms,FK_UFField_UFFieldsets,FK_UFFieldConditionRules_UFFieldConditions,FK_UFFieldConditionRules_UFFields,FK_UFFieldConditions_UFFields,FK_UFFieldsets_UFPages,FK_UFFieldSettings_UFFields,FK_UFForms_UFDataSources,FK_UFPages_UFForms,FK_UFPrevalues_UFFields,FK_UFPrevalueSettings_UFPrevalueProviders,FK_UFRecordDataBit_UFRecordFields,FK_UFRecordDataDateTime_UFRecordFields,FK_UFRecordDataInteger_UFRecordFields,FK_UFRecordDataLongString_UFRecordFields,FK_UFRecordDataString_UFRecordFields,FK_UFRecordFields_UFFields,FK_UFRecordFields_UFRecords,FK_UFRecords_UFForms,FK_UFRecordsXml_UFForms,FK_UFUserFormSecurity_UFForms,FK_UFWorkflowExecutionStates_UFFormStates,FK_UFWorkflows_UFForms,FK_umbracoMacroProperty_umbracoMacroPropertyType,FK_umbracoNode_umbracoNode,FK_umbracoUser2app_umbracoUser,FK_user_userType,FK_user2userGroup_user,FK_user2userGroup_userGroup,FK_umbracoNode_umbracoNode_id,FK_cmsTemplate_cmsTemplate,FK_cmsContent_umbracoNode_id,FK_cmsContentVersion_cmsContent_nodeId,FK_cmsDocument_umbracoNode_id,FK_cmsDocument_cmsContent_nodeId,FK_cmsDocument_cmsTemplate_nodeId,FK_cmsContentType_umbracoNode_id,FK_cmsDocumentType_cmsContentType_nodeId,FK_cmsDocumentType_umbracoNode_id,FK_cmsDocumentType_cmsTemplate_nodeId,FK_cmsDataType_umbracoNode_id,FK_cmsDataTypePreValues_cmsDataType_nodeId,FK_cmsLanguageText_cmsDictionary_id,FK_umbracoDomains_umbracoNode_id,FK_cmsMacroProperty_cmsMacroPropertyType_id,FK_cmsMacroProperty_cmsMacro_id,FK_cmsMemberType_umbracoNode_id,FK_cmsMemberType_cmsContentType_nodeId,FK_cmsMember_cmsContent_nodeId,FK_cmsMember_umbracoNode_id,FK_cmsMember2MemberGroup_cmsMember_nodeId,FK_cmsMember2MemberGroup_umbracoNode_id,FK_cmsContentXml_cmsContent_nodeId,FK_cmsPreviewXml_cmsContent_nodeId,FK_cmsPreviewXml_cmsContentVersion_VersionId,FK_cmsPropertyTypeGroup_cmsPropertyTypeGroup_id,FK_cmsPropertyTypeGroup_cmsContentType_nodeId,FK_cmsPropertyType_cmsDataType_nodeId,FK_cmsPropertyType_cmsContentType_nodeId,FK_cmsPropertyType_cmsPropertyTypeGroup_id,FK_cmsPropertyData_umbracoNode_id,FK_cmsPropertyData_cmsPropertyType_id,FK_umbracoRelation_umbracoNode,FK_umbracoRelation_umbracoNode1,FK_umbracoRelation_umbracoRelationType_id,FK_cmsStylesheet_umbracoNode_id,FK_cmsTagRelationship_umbracoNode_id,FK_cmsTagRelationship_cmsTags_id,FK_umbracoUser_umbracoUserType_id,FK_cmsTask_cmsTaskType_id,FK_cmsTask_umbracoNode_id,FK_cmsTask_umbracoUser,FK_cmsTask_umbracoUser1,FK_cmsContentType2ContentType_umbracoNode_parent,FK_cmsContentType2ContentType_umbracoNode_child,FK_cmsContentTypeAllowedContentType_cmsContentType,FK_cmsContentTypeAllowedContentType_cmsContentType1,FK_umbracoUser2app_umbracoUser_id,FK_umbracoUser2NodeNotify_umbracoUser_id,FK_umbracoUser2NodeNotify_umbracoNode_id,FK_umbracoUser2NodePermission_umbracoUser_id,FK_umbracoUser2NodePermission_umbracoNode_id,PK__cmsConte__3213E83F45F365D3,PK__MediaPro__5E548648AEBEA0C3,PK__sysdiagr__C2B05B61114A936A,PK_CMSImportCustomRelation,PK_CMSImportMediaRelation,PK_CMSImportRelation,PK_CMSImportScheduledItems,PK_CMSImportScheduledTask,PK_CMSImportState,PK_cmsTab,PK_domains,PK_icUrlTracker,PK_infocaster301,PK_language,PK_LookWhosEditingNow,PK_macro,PK_macroProperty,PK_macroPropertyType,PK_StandardValues,PK_stylesheetProperty,PK_templates,PK_UCUserSettings,PK_UFDataSourceMappings,PK_UFDataSources,PK_UFField,PK_UFFieldConditionRules,PK_UFFieldConditions,PK_UFFieldsets,PK_UFForms,PK_UFFormStates,PK_UFPages,PK_UFPrevalueProviders,PK_UFPrevalues,PK_UFPrevalueSettings,PK_UFRecordFields,PK_UFRecords,PK_UFRecordsXml,PK_UFUserFormSecurity,PK_UFUserSecurity,PK_UFWorkflowExecutionStates,PK_UFWorkflows,PK_UFWorkflowsToForms,PK_umbracoStartSession,PK_umbracoStatEntry,PK_umbracoStylesheet,PK_user2userGroup,PK_userGroup,PK_userType,PK_cmsTemplate,PK_cmsContentVersion,PK_umbracoLanguage,PK_umbracoDomains,PK_cmsMacro,PK_cmsMacroPropertyType,PK_cmsMacroProperty,PK_cmsMember,PK_cmsPropertyTypeGroup,PK_cmsStylesheet,PK_cmsStylesheetProperty,PK_umbracoUserType,IX_umbracoNodeTrashed,IX_umbracoNodeParentId,IX_umbracoNodeObjectType,IX_cmsTemplate_nodeId,IX_cmsContent,IX_cmsContentVersion_ContentId,IX_cmsContentVersion_VersionId,IX_cmsDocument,IX_cmsDocument_published,IX_cmsDocument_newest,IX_cmsContentType,IX_cmsContentType_icon,IX_cmsDataType_nodeId,IX_cmsDictionary_id,IX_umbracoLanguage_languageISOCode,IX_umbracoLog,IX_cmsPropertyData,IX_cmsPropertyData_1,IX_cmsPropertyData_2,IX_cmsPropertyData_3,IX_umbracoUserLogins_Index,IX_umbracoUser_userLogin,IX_cmsTaskType_alias,IX_computerName,IX_umbracoServer_isActive

 

The following indexes were found in the database, but are not in the current schema:

UK_principal_name,IX_umbracoLog_datestamp,IX_umbracoLog_Header,IX_umbracoLog_userid

 

The following unknown constraints (Primary Keys, Foreign Keys and Indexes) were found in the database, but are not in the current schema:

cmsTags_cmsTagRelationship,UK_principal_name,umbracoNode_cmsTagRelationship

 

 

2014-06-11 15:01:22,193 [6] ERROR Umbraco.Core.UmbracoApplicationBase - [Thread 39] An unhandled exception occurred

System.ArgumentOutOfRangeException: startIndex cannot be larger than length of string.

Parameter name: startIndex

   at System.String.InternalSubStringWithChecks(Int32 startIndex, Int32 length, Boolean fAlwaysCopy)

   at System.String.Substring(Int32 startIndex)

   at uComponents.UI.ItemInfoService.ProcessRequest(HttpApplication app)

   at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()

   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

 

I had the same problem: the database step hangs at 90%, in my case no error was reported, but looking at the umbraco log ,I get this:

Database configuration status: Upgrade completed! INFO

Completed resolution of types of umbraco.interfaces.ITree, foun... INFO
Starting resolution types of umbraco.interfaces.ITree INFO
Completed resolution of types of umbraco.interfaces.IDataType, ... INFO
Starting resolution types of umbraco.interfaces.IDataType INFO
Cleared 0 items from the media xml cache that were trashed and ... INFO
Executing sql statement 1: ALTER TABLE [umbracoUser] ALTER COLU... INFO
Added UPGRADE migration 'AddChangeDocumentTypePermission' to co... INFO
Added UPGRADE migration 'UpdateToNewMemberPropertyAliases' to c... INFO
Added UPGRADE migration 'ChangePasswordColumn' to context INFO
Added UPGRADE migration 'AdditionalIndexesAndKeys' to context INFO
Database upgrade started INFO
Running 'Upgrade' service INFO
Added UPGRADE migration 'AssignMissingPrimaryForMySqlKeys' to c... INFO
Added UPGRADE migration 'AssignMissingPrimaryForMySqlKeys2' to ... INFO
Initializing database migrations INFO
Database requires upgrade INFO
Running 'Install' service INFO
Database configuration status: Started INFO

We force the end of the install going to [HOST]/install/default.aspx?installStep=theend, after we see the "Upgrade completed!", assuming that is a callback response to the ajax of the DB step. So the backend is available again.

I guess that at some point the wizard installer stop working.

I had the same experience. It seems that the issue is caused by missing permissions. You need to update the permissions on the newly uploaded web.config-file to make it possible for the upgarde procedure to finish by updating the status. At least that worked for me.

is working on a reply...