There are certain pages in SharePoint 2010 Central Administration that will throw an "Error on Page" error when you are browsing with Internet Explorer 8 and you try to perform an action.
For example, when trying to edit a user profile synchronization connection:
To get around this you can either use a different browser, or from the page that's causing the error you can do the following:
- Launch Internet Explorer 8 and browse to the page that's throwing the error
- Press F12 to open the Developer Tools
- Set the Browser Mode: to IE7
- Close the Developer Tools and try again