A common problem occur for users while playing webex recording in Windows 8 running IE 10 or Chrome. Error message something like:C:\PROGRA~3\WebEx\WebEx\500\atinst.exeWindows cannot find 'C:\PROGRA~3\WebEx\WebEx\500\atinst.exe'. Make sure you typed the name correctly, and then try again.

There is no fix as of now, but a quick dirty way is as under:1. Open IE 10 2. Select tools (Alt+X) which is at top right corner 3. Select option F12 developer tools. This will popup developers tools window at the bottom of the browser 4. Select Tools ---> Change user agent string -> IE9 Now start webex recorded session, it will work. My problem got resolved, hope this work for you too!