Had this issue today.
The local admin had for some reason re-installed W2K over the top without telling anyone.
ICA seemed to be up and running and listening but client could not connect.
Nothing in event logs and nothing on client log.
RDP could log in ok.
I'm guessing that W2K overwrote something vital.
'Fix' was to remove and reinstall metaframe.
Unfortunately you then have to reapply all the hotfixes but it did get it up and running and serving clients until I can get some downtime.
The local admin had for some reason re-installed W2K over the top without telling anyone.
ICA seemed to be up and running and listening but client could not connect.
Nothing in event logs and nothing on client log.
RDP could log in ok.
I'm guessing that W2K overwrote something vital.
'Fix' was to remove and reinstall metaframe.
Unfortunately you then have to reapply all the hotfixes but it did get it up and running and serving clients until I can get some downtime.