Hello,

Client install issues can be caused by many different settings and issues within the system and interaction within the network. I would try some of the following basic trouble shooting checks an if they do not fix your issues, I would suggest opening a support case with your support group.

First I would check that the settings in IE haven't changed any from the last time you used it (active x, DEP turned on, firewalls installed, and new anti-virus as well as IE settings).
Next make sure that you are using a supported browser (IE 10 and anything IE 64 bit are not supported, as well as CHrome, Firefox, and Safari are not supported).
I would try to install utilizing Administration mode (right click on the IE icon prior to launching, and select ''run as administrator'' option) for the initial installation.
If these do not work make sure that you have read/write capability to the user folders and those under it, as it will be required to complete the installation.

If none of these work, I would try to install the QC Explorer and see if you still have issues?

If after exhausting these options, I would open a case with your support group to trouble shoot the issues.

Hope this helps?