This could be several things. I would check to make sure that you are not blocking active X on the system. I would try and perform a clean removal of the QC client from the machine and then reinstall it again afterward. To perform a clean uninstall, and clean the system of errant files follow these steps:

Delete the following file under the following directory and then open a new browser and log into
Quality Center.
a) C:Documents and SettingsLocal SettingsApplication DataMercury
InteractiveQuality CenterQCClient.config)
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?Clear the Client Cache Folder
1) Close all browsers on the PC.
a) Also, Check in Task Manager for any orphaned iexplore.exe processes. End any you find.
2) Now open a file explorer and in the address bar type in: %temp% (hit enter)
3) This will take you to a directory like: C:Documents and Settingsyour_user_nameLocal
SettingsTemp
4) Delete the TD_80 directory there.

Clear the QC Client ConfigurationFolder
Delete the following file under the following directory and then open a new browser and log into Quality ?Center.
1) C:Documents and SettingsLocal SettingsApplication DataMercury
InteractiveQuality CenterQCClient.config
Uninstall the QC Client (Perform one of these to uninstall)
If the C:Program FilesCommon FilesMercury Interactive DOES NOT exist
1) Navigate to the Control Panel
2) Add or Remove Programs
3) Uninstall - Quality Center Client Side and Reboot the PC
4) Upon successful removal of the Quality Center Client Side
5) Launch Quality Center, you will see all the activeX controls being loaded.

Otherwise If the C:Program FilesCommon FilesMercury Interactive EXISTS then
1) Close ALL internet explorer browser sessions.
2) Navigate to C:Program FilesCommon Files
3) Delete the ''Mercury Interactive'' directory. If an error occurs, launch Task Manager and kill all
iexplorer.exe processes and try again.
4) Upon successful deletion of the ''Mercury Interactive'' directory, Launch Quality Center, you will
see all the activeX controls being loaded.
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Hope this helps.?
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