Create a UDL (Microsoft data link) from the desktop on the machine. Try and connect to the server using the sql driver and nt security. Then use the test...

Are there any firewalls between the two machines blocking port 1433?

When you checked the 'Client Network Utility'

was TCP-IP the top of the protocols list?

If not move it to the top

Are you connecting via name or IP. If you are connecting via name try using the IP instead.

Have you checked the protocol's of both machines?

did leave Enterprise Manager running on the server did you?

Because it has been know on previous versions to tie up memory with its memory leaks, which can cause problems.

...

Did you change the machine name? If so it will give you that error.

As far as I know you will need to reinstall to get it working again.

As far as I remember

Access uses Microsoft Jet (part of MDAC), and Excel uses Microsoft Query to access SQL (among other things). MS Query which uses MDAC as well.

If...

Office will install MDAC. Did you reboot prior to installing SQL, or where any services running which could have locked them?

Last time I had MDAC locked I managed to get...

what error message did you get when it failed?

One possibility could be that the MDAC files were locked. Don't forget SR1 for SQL (it upgrades the MDAC version to 2.6sp1)

...

ASPEMAIL also have written a sql sp so their software can be used with sql server. I have not used it myself via sql as I use outlook, but I...

How about backing up your model database (just in case), and restoring a copy of the model database from another server which is on the same service pack).

Then create a...

Got a copy of it yesterday. I'll let you know if I get round to looking at it soon.

In the past I have removed the Builtin/Administrator from the SA role. But I have found that they have logins within each database, where they are dbo (and cannot be...

Also empty the recycle bin, if there is somthing in it.