Symptom:
When trying to edit a survey in Ultimate Survey Enterprise survey software via Internet Explorer, an error is thrown that looks similar to the following:

Server Error in '/UltimateSurvey' Application.
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A field or property with the name 'Category Text' was not found on the selected datasource.
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.Web.HttpException: A field or property with the name 'CategoryText' was not found on the selected datasource.

Cause:
One or more of the matrix questions in Ultimate Survey have been corrupted.

Resolution:
1. Log out of Ultimate Survey.
2. Run the following script in query analyzer

update rz_matrixcategory set categorytext = '' where categorytext is null
3. Log in to Ultimate Survey and the survey will be fixed.