Very Slow Logon Speed

Check your server, look for /profile/username/ if you don't find ALL of your users /my documents/, or even outlook .pab or .pst.

If found, your user's logon copy all of the user's documents. Often seen when an exchange server is running.

You'll have to move user's documents, and messages, to another directory. And clean your server storage...

Check to make sure that someone isn't running a network game or game server through your network, specially if it is on a 24/7 Internet connection, you could look for MUD's.

Alternatively, check out SiSoft Sandra analysis program, it's very useful and the latest additions make me want to upgrade...
http://www.sisoftware.net/sandra/

You could also check that if you have added any new machines, unplug them from the hub one at a time and check the network speed. Maybe one of the cables is wired wrong and is causing the network problems.

Check to make sure that someone isn't running a network game or game server through your network, specially if it is on a 24/7 Internet connection, you could look for MUD's.

Alternatively, check out SiSoft Sandra analysis program, it's very useful and the latest additions make me want to upgrade...
http://www.sisoftware.net/sandra/

You could also check that if you have added any new machines, unplug them from the hub one at a time and check the network speed. Maybe one of the cables is wired wrong and is causing the network problems.

What kind of name resolution are you doing? Can you ping by both IP address and name?

Are you using group policy? Has something in group policy changed? What about log on scripts, have any been added or changed recently? Have you recently turned on Auditing? If so you may be auditing way too much.

Restart all workstations, and preferably the server as well.

Are there any errors showing in the system or application event logs on the server or the workstations?

Hope some of thishelps. Good luck,