Are you following this documentation on how to migrate from v7 to v8?: https://our.umbraco.com/documentation/getting-started/setup/upgrading/migrating-to-v8

Regards, Magnus

yes i am

I think I've had the same problem, but before I suggest a fix let's check that you're not getting the same message from a different part of the migration process.

There should be another line in the log with more details of where the exception happened, probably shortly before the one you quoted. Searching the log for "An item with the same key has already been added" should find it.

hi Steve is this what you requested to see?

{"@t":"2019-10-02T07:02:08.2091160Z","@mt":"The database schema validation produced the following summary: {DbSchemaSummary}","DbSchemaSummary":"The following tables were found in the database, but are not in the current schema:\r\ncmsTask,cmsContent,cmsContentVersion,cmsDocument,cmsMedia,cmsDataType,cmsDataTypePreValues,umbracoMigration,umbracoDomains,cmsContentXml,cmsPreviewXml,cmsPropertyData,cmsTaskType,umbracoContent,umbracoContentVersion,umbracoMediaVersion,umbracoDocument,umbracoDataType,umbracoDomain,umbracoPropertyData,cmsContentNu,umbracoDocumentVersion,umbracoKeyValue,umbracoContentVersionCultureVariation,umbracoDocumentCultureVariation,umbracoContentSchedule\r\n \r\nThe following columns were found in the database, but are not in the current schema:\r\ncmsTask,closed,cmsTask,id,cmsTask,taskTypeId,cmsTask,nodeId,cmsTask,parentUserId,cmsTask,userId,cmsTask,DateTime,cmsTask,Comment,cmsTemplate,design,cmsContent,pk,cmsContent,nodeId,cmsContent,contentType,cmsContentVersion,id,cmsContentVersion,ContentId,cmsContentVersion,VersionId,cmsContentVersion,VersionDate,cmsDocument,nodeId,cmsDocument,published,cmsDocument,documentUser,cmsDocument,versionId,cmsDocument,text,cmsDocument,releaseDate,cmsDocument,expireDate,cmsDocument,updateDate,cmsDocument,templateId,cmsDocument,newest,cmsMedia,nodeId,cmsMedia,versionId,cmsMedia,mediaPath,cmsDataType,pk,cmsDataType,nodeId,cmsDataType,propertyEditorAlias,cmsDataType,dbType,cmsDataTypePreValues,id,cmsDataTypePreValues,datatypeNodeId,cmsDataTypePreValues,value,cmsDataTypePreValues,sortorder,cmsDataTypePreValues,alias,umbracoMigration,id,umbracoMigration,name,umbracoMigration,createDate,umbracoMigration,version,umbracoDomains,id,umbracoDomains,domainDefaultLanguage,umbracoDomains,domainRootStructureID,umbracoDomains,domainName,cmsMacro,macroScriptType,cmsMacro,macroScriptAssembly,cmsMacro,macroXSLT,cmsMacro,macroPython,cmsContentXml,nodeId,cmsContentXml,xml,cmsPreviewXml,nodeId,cmsPreviewXml,versionId,cmsPreviewXml,timestamp,cmsPreviewXml,xml,cmsPropertyData,id,cmsPropertyData,contentNodeId,cmsPropertyData,versionId,cmsPropertyData,propertytypeid,cmsPropertyData,dataInt,cmsPropertyData,dataDecimal,cmsPropertyData,dataDate,cmsPropertyData,dataNvarchar,cmsPropertyData,dataNtext,cmsTags,ParentId,cmsTaskType,id,cmsTaskType,alias,cmsContentType,isElement,cmsContentType,variations,umbracoContent,nodeId,umbracoContent,contentTypeId,umbracoContentVersion,id,umbracoContentVersion,nodeId,umbracoContentVersion,versionDate,umbracoContentVersion,userId,umbracoContentVersion,current,umbracoContentVersion,text,umbracoMediaVersion,id,umbracoMediaVersion,path,umbracoDocument,nodeId,umbracoDocument,published,umbracoDocument,edited,umbracoDataType,nodeId,umbracoDataType,propertyEditorAlias,umbracoDataType,dbType,umbracoDataType,config,umbracoLanguage,isDefaultVariantLang,umbracoLanguage,mandatory,umbracoLanguage,fallbackLanguageId,umbracoDomain,id,umbracoDomain,domainDefaultLanguage,umbracoDomain,domainRootStructureID,umbracoDomain,domainName,umbracoLog,entityType,umbracoLog,parameters,cmsMacro,macroSource,cmsMacro,macroType,cmsPropertyType,variations,umbracoPropertyData,id,umbracoPropertyData,versionId,umbracoPropertyData,propertyTypeId,umbracoPropertyData,languageId,umbracoPropertyData,segment,umbracoPropertyData,intValue,umbracoPropertyData,decimalValue,umbracoPropertyData,dateValue,umbracoPropertyData,varcharValue,umbracoPropertyData,textValue,cmsTags,languageId,umbracoRedirectUrl,culture,cmsContentNu,nodeId,cmsContentNu,published,cmsContentNu,data,cmsContentNu,rv,umbracoDocumentVersion,id,umbracoDocumentVersion,templateId,umbracoDocumentVersion,published,umbracoKeyValue,key,umbracoKeyValue,value,umbracoKeyValue,updated,umbracoContentVersionCultureVariation,id,umbracoContentVersionCultureVariation,versionId,umbracoContentVersionCultureVariation,languageId,umbracoContentVersionCultureVariation,name,umbracoContentVersionCultureVariation,date,umbracoContentVersionCultureVariation,availableUserId,umbracoDocumentCultureVariation,id,umbracoDocumentCultureVariation,nodeId,umbracoDocumentCultureVariation,languageId,umbracoDocumentCultureVariation,edited,umbracoDocumentCultureVariation,available,umbracoDocumentCultureVariation,published,umbracoDocumentCultureVariation,name,umbracoContentSchedule,id,umbracoContentSchedule,nodeId,umbracoContentSchedule,languageId,umbracoContentSchedule,date,umbracoContentSchedule,action\r\n \r\nThe following constraints (Primary Keys, Foreign Keys and Indexes) were found in the database, but are not in the current schema:\r\nFK_cmsContent_cmsContentType_nodeId,FK_cmsContent_umbracoNode_id,FK_cmsContentVersion_cmsContent_nodeId,FK_cmsContentXml_cmsContent_nodeId,FK_cmsDataType_umbracoNode_id,FK_cmsDataTypePreValues_cmsDataType_nodeId,FK_cmsDocument_cmsContent_nodeId,FK_cmsDocument_cmsTemplate_nodeId,FK_cmsDocument_umbracoNode_id,FK_cmsMedia_cmsContent_nodeId,FK_cmsMedia_umbracoNode_id,FK_cmsMember_cmsContent_nodeId,FK_cmsMember_umbracoNode_id,FK_cmsPreviewXml_cmsContent_nodeId,FK_cmsPreviewXml_cmsContentVersion_VersionId,FK_cmsPropertyData_cmsPropertyType_id,FK_cmsPropertyData_umbracoNode_id,FK_cmsPropertyType_cmsDataType_nodeId,FK_cmsTags_cmsTags,FK_cmsTask_cmsTaskType_id,FK_cmsTask_umbracoNode_id,FK_cmsTask_umbracoUser,FK_cmsTask_umbracoUser1,FK_umbracoDomains_umbracoNode_id,FK_umbracoNode_umbracoUser_id,FK_umbracoContent_umbracoNode_id,FK_umbracoContent_cmsContentType_NodeId,FK_umbracoContentVersion_umbracoContent_nodeId,FK_umbracoContentVersion_umbracoUser_id,FK_umbracoMediaVersion_umbracoContentVersion_id,FK_umbracoDocument_umbracoContent_nodeId,FK_umbracoDataType_umbracoNode_id,FK_umbracoLanguage_umbracoLanguage_id,FK_umbracoDomain_umbracoNode_id,FK_umbracoLog_umbracoUser_id,FK_cmsMember_umbracoContent_nodeId,FK_cmsPropertyType_umbracoDataType_nodeId,FK_umbracoPropertyData_umbracoContentVersion_id,FK_umbracoPropertyData_cmsPropertyType_id,FK_umbracoPropertyData_umbracoLanguage_id,FK_cmsTags_umbracoLanguage_id,FK_cmsContentNu_umbracoContent_nodeId,FK_umbracoDocumentVersion_umbracoContentVersion_id,FK_umbracoDocumentVersion_cmsTemplate_nodeId,FK_umbracoContentVersionCultureVariation_umbracoContentVersion_id,FK_umbracoContentVersionCultureVariation_umbracoLanguage_id,FK_umbracoContentVersionCultureVariation_umbracoUser_id,FK_umbracoDocumentCultureVariation_umbracoNode_id,FK_umbracoDocumentCultureVariation_umbracoLanguage_id,FK_umbracoContentSchedule_umbracoContent_nodeId,FK_umbracoContentSchedule_umbracoLanguage_id,PK_cmsContent,PK_cmsContentPreviewXml,PK_cmsContentVersion,PK_cmsContentXml,PK_cmsDataType,PK_cmsDataTypePreValues,PK_cmsDocument,PK_cmsMedia,PK_cmsPropertyData,PK_cmsTask,PK_cmsTaskType,PK_structure,PK_umbracoDomains,PK_umbracoMigration,PK_umbracoNode,PK_umbracoContent,PK_umbracoContentVersion,PK_umbracoMediaVersion,PK_umbracoDocument,PK_umbracoDataType,PK_umbracoDomain,PK_umbracoPropertyData,PK_cmsContentNu,PK_umbracoDocumentVersion,PK_umbracoKeyValue,PK_umbracoContentVersionCultureVariation,PK_umbracoDocumentCultureVariation,PK_umbracoContentSchedule\r\n \r\nThe following indexes were found in the database, but are not in the current schema:\r\nIX_cmsContent,IX_cmsContentVersion_ContentId,IX_cmsContentVersion_VersionId,IX_cmsDataType_nodeId,IX_cmsDocument,IX_cmsDocument_newest,IX_cmsDocument_published,IX_cmsMedia,IX_cmsPropertyData_1,IX_cmsPropertyData_2,IX_cmsPropertyData_3,IX_cmsTaskType_alias,IX_umbracoMigration,IX_umbracoNodeObjectType,IX_umbracoNodeParentId,IX_umbracoNodePath,IX_umbracoNodeTrashed,IX_umbracoNodeUniqueID,IX_umbracoNode_UniqueId,IX_umbracoNode_ParentId,IX_umbracoNode_Path,IX_umbracoNode_Trashed,IX_umbracoNode_ObjectType,IX_umbracoMediaVersion,IX_umbracoDocument_Published,IX_umbracoLanguage_fallbackLanguageId,IX_umbracoPropertyData_VersionId,IX_umbracoPropertyData_PropertyTypeId,IX_umbracoPropertyData_LanguageId,IX_umbracoPropertyData_Segment,IX_cmsTags_LanguageId,IX_umbracoUserLogin_lastValidatedUtc,IX_umbracoContentVersionCultureVariation_VersionId,IX_umbracoContentVersionCultureVariation_LanguageId,IX_umbracoDocumentCultureVariation_NodeId,IX_umbracoDocumentCultureVariation_LanguageId\r\n \r\n","SourceContext":"Umbraco.Core.Migrations.Install.DatabaseBuilder","ProcessId":5076,"ProcessName":"w3wp","ThreadId":7,"AppDomainId":2,"AppDomainAppId":"LMW3SVC2ROOT","MachineName":"VMWEBCMSLAB3","Log4NetLevel":"INFO ","HttpRequestNumber":9,"HttpRequestId":"a8e74b7c-3e64-4ec2-aa0c-e11d49a1aaba"}

Hi Blago

please reffer to this : https://github.com/umbraco/Umbraco-CMS/issues/6588 the query's that stevemegson shared helped us.

thanks E

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