I have a lot of users that can not update their display preferences. When they try to change any of the values they get the following error: Invalid Textarea value.Please use your back button to return to the previous page.

Any ideas?

Have you upgraded recently? Make sure all files, including all template files have been uploaded.

It was a fresh install of 6.5.1.1. I guess I could try upgrading to 6.5.2 tonight.

The weird thing is that I can change my values and not get the error but no one else seems to be able do this.

I believe that was a bug in 6.5.1.1, there were several issues with form validation. 6.5.2 should correct it I believe.