When we go to add a new product the Product Variant tab is missing. The rest of the tabs are there. I believe this has something to do with ajaxtoolkit but I'm not sure where to go from here. Using version 1.90 We are getting two Error below. I know Error 2 is because of the missing tab.

Error 1

Server Error in '/' Application.
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Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[NullReferenceException: Object reference not set to an instance of an object.]
   NopSolutions.NopCommerce.Web.Administration.Modules.ProductVariantAttributesControl.OnInit(EventArgs e) +57
   System.Web.UI.Control.InitRecursive(Control namingContainer) +140
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Control.AddedControl(Control control, Int32 index) +197
   System.Web.UI.ControlCollection.Add(Control child) +79
   AjaxControlToolkit.TabPanel.OnInit(EventArgs e) +139
   System.Web.UI.Control.InitRecursive(Control namingContainer) +140
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Control.InitRecursive(Control namingContainer) +311
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +480

Error 2

Server Error in '/' Application.
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Cannot insert the value NULL into column 'ProductVariantId', table 'xxxxxx.dbo.Nop_ProductVariant'; column does not allow nulls. INSERT fails.
The statement has been terminated.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.SqlClient.SqlException: Cannot insert the value NULL into column 'ProductVariantId', table 'xxxxxxxx.dbo.Nop_ProductVariant'; column does not allow nulls. INSERT fails.
The statement has been terminated.

Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[SqlException (0x80131904): Cannot insert the value NULL into column 'ProductVariantId', table 'xxxxxxxxx.dbo.Nop_ProductVariant'; column does not allow nulls. INSERT fails.
The statement has been terminated.]
   System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection) +2062078
   System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +5050204
   System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning() +234
   System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2275
   System.Data.SqlClient.SqlDataReader.ConsumeMetaData() +33
   System.Data.SqlClient.SqlDataReader.get_MetaData() +86
   System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString) +311
   System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async) +987
   System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result) +162
   System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method) +32
   System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method) +141
   System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior) +12
   System.Data.Common.DbCommand.ExecuteReader(CommandBehavior behavior) +10
   System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary`2 identifierValues, List`1 generatedValues) +8158468
   System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter) +267

[UpdateException: An error occurred while updating the entries. See the inner exception for details.]
   System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter) +389
   System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache) +163
   System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options) +609
   System.Data.Objects.ObjectContext.SaveChanges() +15
   NopSolutions.NopCommerce.BusinessLogic.Audit.LogService.InsertLog(LogTypeEnum logType, Int32 severity, String message, Exception exception, String IPAddress, Int32 customerId, String pageUrl) +845
   NopSolutions.NopCommerce.BusinessLogic.Audit.LogService.InsertLog(LogTypeEnum logType, String message, Exception exception) +215
   NopSolutions.NopCommerce.Web.BaseNopAdministrationUserControl.ProcessException(Exception exc, Boolean showError) +84
   NopSolutions.NopCommerce.Web.BaseNopAdministrationUserControl.ProcessException(Exception exc) +40
   NopSolutions.NopCommerce.Web.Administration.Modules.ProductAddControl.SaveButton_Click(Object sender, EventArgs e) +185
   System.Web.UI.WebControls.Button.OnClick(EventArgs e) +118
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +112
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5563