Try another PDF reader like FoxitReader if you can. Also clear all temp & cache files. Check for BHO add-ins (browser helper objects) that may be causing a conflict. Disable them and see if that changes any behavior.
Just in case anyone else has a similar problem.
The problem was between the ciscos PIX firewall and the new HP ProCurve switches that were installed. The autosensing ports were not connecting correctly. Once we set the ports between the two to full duplex everything worked fine. We’re in the process of setting everything we have to full duplex rather than autosensing so this doesn’t happen in the future with other devices. We’re hoping it will also improve our network speed by helping create less packet loss.
Completely agree with this!! especially the first part of it. Not so up on the last part, but by simply changing your browser and clearing your cache files seems to help with the ensuing problems you were having.