Like many other people on the internet I had to use Cisco VPN Client to connect to our network. First Cisco didn't support 64 bit, now they do support, but I am unable to install the 64bit client. I get this error during the installation:
Installation ended prematurely because of an error.
Well I am using Shrew VPN Client which is freeware and allows to import the Cisco Client pcf configuration files.
After the import and first try to connect it ended up just with "bringing up tunnel ...".
I had to make one more manual step: Uncheck and Check again the Shrew Soft Lightweight Filter on the connection properties tab. (Configure the connection which connects you to internet).
After that everything worked ok for me.