I've got an issue that seems to be happening more and more frequently. We run Exchange 2000 on a Windows 2000 DC. My users use both Outlook 2003 and 2007. I keep hearing that users cannot connect to Exchange upon first opening up Outlook and the only way to fix it seems to be to reboot their PC and then reopen Outlook. Is this an issue that lies with the Exchange server? I reboot the server about once a month but that doesn't seem to really help the issue.