On a 100 device NT4 domain - with a 2003 based WSUS 2 server talking to W2K
clients.
A few workstations just decided not to talk to the server any more.  Their
WSUS log has an entry saying  
2008-04-29 14:13:34:226 1200 6e4 Misc WARNING: Error: 0x80092026 when
verifying trust for
C:\WINNT\SoftwareDistribution\SelfUpdate\Default\wuident.cab

From that point on, even if I re-install the WSUS client it registeres with
the server but then will not talk to it to find out what updates it needs.
This affects approx 10% of my workstations, each at slightly different
update stages, and I am at a loss on how to get these talking again.  50%
plus of my devices have ALL updates downloaded the remaining 40% are nearly
there and this 10% are miles away and doing nothing.

The WSUS client diag program gives pass on all but three entries which are
NONE (for winhttp local machine proxy and bypass proxy and autoconfig URL
proxy)

Anyone else seen this?
I have done the usual, detcect now etc etc and deleted registry entries but
nothing