This may be a fairly obscure issue, but it seemed worth mentioning. If you use the Cisco VPN Client to access any networks and are planning to upgrade your PC from Windows XP to Windows Vista, you shouldn’t. As of version 5.0.00.0340, the VPN Client isn’t supported if you’ve done the upgrade. In my case, when I use the client to connect to a network, I totally lose my Internet connection. Disconnecting the client brings it right back. If you’re planning to upgrade, be sure to check to see if there is a new version of the client that will work.
From the revision notes:
vpnclient-win-msi-5.0.00.0340-k9.exe – Windows 2000, XP and Vista – 32bit only.
vpnclient-win-is-5.0.00.0340-k9.exe – Windows 2000 and XP – 32it only.
update-5.0.00.0340-major-k9.zip – 32bit only.
Windows Vista does NOT support the following:
* Upgrades from Windows XP to Vista.
* Start Before Logon
* SmartCard Authentication
* Integrated Firewall
* 64bit support
* Online Help – Provided only in English
UPDATE July 25, 2007 – Yet another release of the VPN Client (Release 5.0.01.0600), but it still doesn’t support a system upgraded to Vista.
UPDATE October 17, 2007 – Yes, another release (5.0.02.0600 BETA) that doesn’t support a system upgraded to Vista. From the release notes: The Cisco VPN Client for Windows Vista does NOT support the following: System upgraded from Windows XP to Vista (clean OS installation required). When will a useful version be available?!?!
UPDATE November 26, 2007 – Version 5.0.02.0090 was released, still having the note that systems upgraded to Vista are not supported.
UPDATE December 4, 2008 – I haven’t needed to think about this issue for quite a while, but I recently had a client give me version 5.0.01.0600, and it is working fine on my Vista laptop. I don’t know what might make it different than the previous versions that I have tested, but it is nice that it just worked without any headaches.