An Error Occurred in the Script on This Page

An error occurred in the script on this page in CRM 2011.

You might have users that are complaining about Script errors suddenly appearing in Microsoft Dynamics CRM 2011.

The Script error messages looks similar to this.
An error has occurred in the script on this page
Do you want to continue running scripts on this page?

This can occurre after you install a CRM 2011 Rollup.

To get rid of this script error you just need to delete your temporary internet files in
Internet Explorer

Open Internet Explorer
Go to Tools / Internet Options
click on Delete under Browsing history and make sure Temporary Internet files is checked as the image below shows

The rest can be unchecked so you don't lose any other things you might want to preserve.

As a best practise you should always remove Temporary Internet files after you install Microsoft CRM 2011 Rollups as Microsoft also recommends in their KB Articles for Rollups.

I hope this helps :)