Twice now I have found this error in the logs of a client's SharePoint 2010 servers:
Load control template file /_controltemplates/TaxonomyPicker.ascx failed: Could not load type 'Microsoft.SharePoint.Portal.WebControls.TaxonomyPicker' from assembly 'Microsoft.SharePoint.Portal, Version=188.8.131.52, Culture=neutral, PublicKeyToken=71e9bce111e9429c'.
The initial fix I found was on a Microsoft Knowledge Base page:
This is not causing any issues except for a wrong ULS log message a single time in a web application process life time, the exception is caught and that template file is skipped. This message should be treated as log noise and can be ignored. To change this behavior:
- Navigate to /14/TEMPLATE/ControlTemplates/TaxonomyPicker.ascx user control
- Open the user control in a text editor and locate the first line
- Find the character string , and replace with a comma ‘,’ (without quotes).
- Save the user control
That's all well and good, but it doesn't fix the problem. If you open up this file, you will notice that the character entity """ appears several times instead of the double-quote character it represents. But changing this does not fix the problem either, at least not for everyone.
The fix is to rename the original file to something like "TaxonomyPicker.ascx_disabled".