This issue can also occur because Cisco CallManager Express has a directory entry configured under the telephony service with a double quote. For example:
directory entry 10 2010 name "Axx Byy"
This causes the Cisco CallManager Express to have a line such as ""Axx Bxx"" in the ITSMain page. This causes the web browser, Microsoft Internet Explorer, to complain due to the page error and to not load the Cisco CallManager Express GUI.
In order to resolve this issue, complete these steps:
Clear the browser cache.
Download the latest Cisco CallManager Express GUI files from Cisco Downloads.
Extract the contents of the file to flash as explained in the directions at the top of the page.
Reboot the router.
Caution: Make a backup of the existing files and configuration, and complete the exact steps. Otherwise, extracted files can be corrupted.
Also, if the Cisco CallManager Express has a directory entry configured under the telephony service with a double quote, change it. For example: