@
Audra - maybe your firewall is blocking calibre, although I wouldn't expect calibre to 'freeze' if that were true. Check your firewall settings. Or disable it for a short while and do a test in calibre.
If it's not a firewall issue, try double clicking the calibre.msi and selecting Repair.
If that doesn't overcome the problem, uninstall calibre via the control panel - don't worry you wont lose libraries or settings. Then get a fresh download from
here and reinstall.
Added : but first, see next three posts
BR