The 'long running scripts' error is commonly a problem that crops up in Internet Explorer. The message is intended for people who are developing and testing websites.
In Internet Explorer Click the 'Tools' menu, and then select 'Internet Options'
Click the 'Advanced' tab, select the 'Disable script debugging (Internet Explorer)' and 'Disable script debugging (Other)' check boxes
Clear the 'Display a notification about every script error' check box, and then click OK
See what happens then.