Hi Umbraco,

Today I tried upgrading from version 7.15.3 to version 8.1.1, and in doing this I was following this article. Unfortunately I have stumbled upon this error message:

I went to /App_Data/Logs/ and this is how the last lines of the log file look like. It seems that it's something related to ConvertTinyMceAndGridMediaUrlsToLocalLink but I am not able to figure out what can be wrong.

Can somebody help me, I would really appreciate.

{"@t":"2020-06-24T06:33:07.5285865Z","@mt":"Execute {MigrationType}","MigrationType":"ConvertTinyMceAndGridMediaUrlsToLocalLink","SourceContext":"Umbraco.Core.Migrations.MigrationPlan","ProcessId":39148,"ProcessName":"iisexpress","ThreadId":17,"AppDomainId":10,"AppDomainAppId":"LMW3SVC2ROOT","MachineName":"PC13","Log4NetLevel":"INFO ","HttpRequestNumber":7,"HttpRequestId":"59a7fbed-318e-4eac-b994-843dc8fd397d"} {"@t":"2020-06-24T06:33:22.9894970Z","@mt":"Database configuration failed","@l":"Error","@x":"System.AggregateException: One or more errors related to unexpected data in grid values occurred. --- System.InvalidOperationException: Cannot deserialize the value as json. This can be because the property editor type is changed from another type into a grid. Old versions of the value in this property can have the structure from the old property editor type. This needs to be changed manually before updating the database.\nProperty info: Id = 4, LanguageId = , VersionId = 2, Value = Navigation --- Newtonsoft.Json.JsonReaderException: Error parsing NaN value. Path '', line 1, position 2.\r\n at Newtonsoft.Json.JsonTextReader.ParseNumberNaN(ReadType readType, Boolean matched)\r\n at Newtonsoft.Json.JsonTextReader.ParseValue()\r\n at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)\r\n at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)\r\n at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)\r\n at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)\r\n at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings)\r\n at Umbraco.Core.Migrations.Upgrade.V810.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n --- End of inner exception stack trace ---\r\n --- End of inner exception stack trace ---\r\n at Umbraco.Core.Migrations.Upgrade.V810.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n at Umbraco.Core.Migrations.MigrationBase.Umbraco.Core.Migrations.IMigration.Migrate()\r\n at Umbraco.Core.Migrations.MigrationPlan.Execute(IScope scope, String fromState, IMigrationBuilder migrationBuilder, ILogger logger)\r\n at Umbraco.Core.Migrations.Upgrade.Upgrader.Execute(IScopeProvider scopeProvider, IMigrationBuilder migrationBuilder, IKeyValueService keyValueService, ILogger logger)\r\n at Umbraco.Core.Migrations.Install.DatabaseBuilder.UpgradeSchemaAndData(MigrationPlan plan)\r\n--- (Inner Exception #0) System.InvalidOperationException: Cannot deserialize the value as json. This can be because the property editor type is changed from another type into a grid. Old versions of the value in this property can have the structure from the old property editor type. This needs to be changed manually before updating the database.\nProperty info: Id = 4, LanguageId = , VersionId = 2, Value = Navigation --- Newtonsoft.Json.JsonReaderException: Error parsing NaN value. Path '', line 1, position 2.\r\n at Newtonsoft.Json.JsonTextReader.ParseNumberNaN(ReadType readType, Boolean matched)\r\n at Newtonsoft.Json.JsonTextReader.ParseValue()\r\n at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)\r\n at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)\r\n at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)\r\n at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)\r\n at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings)\r\n at Umbraco.Core.Migrations.Upgrade.V810.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n --- End of inner exception stack trace ---<---\r\n\r\n--- (Inner Exception #1) System.InvalidOperationException: Cannot deserialize the value as json. This can be because the property editor type is changed from another type into a grid. Old versions of the value in this property can have the structure from the old property editor type. This needs to be changed manually before updating the database.\nProperty info: Id = 6, LanguageId = , VersionId = 3, Value = Navigation --- Newtonsoft.Json.JsonReaderException: Error parsing NaN value. Path '', line 1, position 2.\r\n at Newtonsoft.Json.JsonTextReader.ParseNumberNaN(ReadType readType, Boolean matched)\r\n at Newtonsoft.Json.JsonTextReader.ParseValue()\r\n at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)\r\n at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)\r\n at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)\r\n at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)\r\n at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings)\r\n at Umbraco.Core.Migrations.Upgrade.V810.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n --- End of inner exception stack trace ---<---\r\n\r\n--- (Inner Exception #2) System.InvalidOperationException: Cannot deserialize the value as json. This can be because the property editor type is changed from another type into a grid. Old versions of the value in this property can have the structure from the old property editor type. This needs to be changed manually before updating the database.\nProperty info: Id = 17, LanguageId = , VersionId = 9, Value =

810.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n --- End of inner exception stack trace ---<---\r\n\r\n--- (Inner Exception #3) System.InvalidOperationException: Cannot deserialize the value as json. This can be because the property editor type is changed from another type into a grid. Old versions of the value in this property can have the structure from the old property editor type. This needs to be changed manually before updating the database.\nProperty info: Id = 19, LanguageId = , VersionId = 10, Value =

810.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n --- End of inner exception stack trace ---<---\r\n\r\n--- (Inner Exception #4) System.InvalidOperationException: Cannot deserialize the value as json. This can be because the property editor type is changed from another type into a grid. Old versions of the value in this property can have the structure from the old property editor type. This needs to be changed manually before updating the database.\nProperty info: Id = 21, LanguageId = , VersionId = 11, Value =

81_0.ConvertTinyMceAndGridMediaUrlsToLocalLink.Migrate()\r\n --- End of inner exception stack trace ---<---\r\n","SourceContext":"Umbraco.Core.Migrations.Install.DatabaseBuilder","ProcessId":39148,"ProcessName":"iisexpress","ThreadId":17,"AppDomainId":10,"AppDomainAppId":"LMW3SVC2ROOT","MachineName":"PC13","Log4NetLevel":"ERROR","HttpRequestNumber":7,"HttpRequestId":"59a7fbed-318e-4eac-b994-843dc8fd397d"}