When attempting to install the Cisco Systems VPN Client (5.0.6.0160) I received the following error during installation:
Error 27850. Unable to manage networking component. Operating system corruption may be preventing installation.
This reason for the above error was due to exceeding the default number of network filter drivers installed. By default, in Windows 7 this is configured to be 8 and can be set to a value up to he maximum number of 14 by performing the below;
1) Open Registry Editor
2) Browse to the following registry key;
3) Select the REG_DWORD Value MaxNumFilters
4) Change the value (maximum value is 14).
I have since seen this occur when installing Windows XP Mode and Virtual PC 2007, where the installation of Virtual PC 2007 will fail and following a restart will revert the Windows Update process at 98%.