I'm gonna forget this someday.

Needed to get Cisco VPN client 5.0.07.0290 working on Windows 8 (now 8.1 here) and couldn't get it to install.  Ran across this info:

http://idoneitmyself.com/2014/06/20/installing-cisco-vpn-client-5-0-07-0440-k9-vs-5-0-07-0290-on-windows-8-1/

"I initially received an error:  VPN Client install – Error 27850.  Doing some Googling, I found a newer version, 5.0.07.0440-K9, which I found I already had on another Windows 7 PC.  So I decided to try it.  Same error. 

I started mucking with the registry to no avail and then found the secret sauce.  It all has to do with some “Deterministic Networks” drivers.  Apparently Citrix acquired Deterministic Networks some time ago, so the fixes are available on their site.

Download Winfix.exe and DNEUpdate64 (are there still people using 32-bit?) from Citrix (Citrix acquired Deterministic Networks).  Here’s the main page.  http://www.citrix.com/go/lp/dne.html

Winfix:  ftp://files.citrix.com/winfix.exe

DNEUpdate64:  ftp://files.citrix.com/dneupdate64.msi

DNEUpdate 32-bit:  ftp://files.citrix.com/dneupdate.msi

1. Run Winfix and then reboot.
2. Run dneupdate64 (and then I rebooted, not sure if you need to)
3. Download later version of Cisco VPN client (5.0.07.0440).  Again not sure if 5.0.07.0290 will work or not.
4. Put any PCF files in the new Cisco VPN client installation folder so it picks them up or you can import them later.
5. Run the Cisco VPN client installation (it should work fine).

The installation ran fine and the connection was good.  No problems. "