Exchange 2007 OAB Help.

We have just started getting Synchronization errors when outlook tries to download the OAB. The error is:
Not Downloading Office Address book files. A server (URL) Could not be located.

I have tried removing the OAB virtual directory and recreating it but there doesnt seem to be any files in the OAB folder. They are all located in "Program Files\Microsoft\Exchange Server\ExchangeOAB\{long random foldername}\"

I have run this in EMS:
Get-oabvirtualdirectory -Identity "OAB (Default Web Site)" | FL | Out-file -filepath "C:\settings.txt"

and in the text file i have OfflineAddressBooks : {}
where everything else is correct.

Am i missing something, can anyone help me out please.

Thanks

Tim

On a workstation where this is failing:

1. Open Outlook
2. Hold down Ctrl on the keyboard and right-click on the Outlook icon in the system tray
3. Select Test E-Mail Autoconfiguration
4. Fill in your password and run the test, see if that throws up any errors.

Ive tried that already. It says, Autoconfiguration was unable to determine your settings. I have run Test-outllookwebservices and i get a couple of errors:

ID: 1013 When contacting https://ServerFQDN/autodiscover/autodiscover.xml received the error the underlying conneciton was closed. An unexpected error occured on a send.
ID: 1013: When contacing https://serverFQDN/autodiscover/autodiscover.xml received the error authenication failed because the remote party has closed the transport stream.
ID: 1006: Error The autodiscover service could not be contacted.

This is starting to drive me metal and havent got a clue what it is.

got it working now.