Recently I upgraded my Internet Download Manager to latest version, and suddenly my pc became extremely slow when IDM was working. Within few minutes it almost stalled. It felt as if I was being hacked through IDM. Kaspersky, AVG and other programs didn't help. I installed ZoneAlarm, and the problem stopped. Instead, almost all my downloads were corrupted. I have been writing with IDM and they couldn't really help me. At last I uninstalled IDM and re-installed it. Now the problem is close to not existing. So if any of You are experiencing problems with download managers after installing ZoneAlarm, just try to re-install the manager. It's as if it's the easiest way to correct the settings in ZoneAlarm.
Take care out there