This error is quite odd and we have not received such reports so far. Could you confirm whether you are using the latest release build of WebGrid 7 and WebUI.NET Framework 3.0 on your project?

I tried to reproduce the problem in my local test by creating a simple page with WebGrid. The grid binds to a table that has a ‘datetime’ field and enables the sorting feature. My efforts were not successful – the sorting on ‘datetime’ column worked smoothly without any issues.

We are willing to advise you further but in order to do so we would need you to elaborate on your specific scenario and possibly give us a running simple sample which replicates the issue that we can use to observe the problematic behavior.

I enclosed my test page to be evaluated on your end. You may modify the sample so it replicates the issue and then have the sample send back to us for further investigation.