Outlook cannot access Exchange Server over VPN, but Exchange Server is fine

I've been using Outlook 2003 to access our corp Exchange server over a VPN for years. Today, I booted my PC, started Outlook and I get the message in the lower right status bar area: Trying to connect... Well, it never does. The Exchange Server is fine and so is my account. I know this because I can remote desktop into my office PC, start the same version of Outlook on that PC and it all works fine. I can also ping the Exchange Server over the VPN by its network name and it resolves to its IP address and responds just fine. I have recreated my Outlook profile because I know these get corrupted from time to time but that didn't fix it this time. I also tried an Office repair using the installer and that didn't help either. Ideas anyone???
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tcianfloneAuthor Commented:
Oh, I also ran a scan of the OST using SCANPST. If found and corrected some errors. And now, after Outlook sitting there for 10 minutes, it finally connected. Exit Outlook, restart, and it's saying Trying to connect again. Very odd. Also very interesting, SCANOST takes a long time to connect to the Exchange Server too, but not nearly as long as Outlook.
Have you taken any Windows or AV Updates at or about the time this problem started? Just to check...does it connect if you turn off the Windows Firewall and any AV you have on the system?
Paul SolovyovskySenior IT AdvisorCommented:
Check the connection between the two sites, if the connection is slow it may cause this.  Good test is to try to access OWA on the exchange server, this will definately give you an idication whether there are any issues with your mailbox.  If OWA is slow or not working it could be an indication of a slow network connection as well
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tcianfloneAuthor Commented:
I just now disabled both antivirus and antispyware. No improvement with Outlook.
And you haven't downloaded any Windows Updates?

You might need to try and uninstall/reinstall Outlook and see if that fixes it.
Paul SolovyovskySenior IT AdvisorCommented:
I would not uninstall/reinstall outlook.  If your outlook profile is removed you may have problems re-establishing it over vpn.

have you tried accessing via OWA to the internal URL over the VPN?
tcianfloneAuthor Commented:
We don't run OWA here. Meantime, a new wrinkle! I talked with another employee who works from home and he's having the EXACT same problem, both started at the same time, early today. So now I'm thinking it's a networking/server issue back on the office LAN. So I tried replacing the DSL Router up there with one of our spares, no change. I rebooted the Exchange/Domain server, no change. No Exchange error messages in the App Event log either. So I have TWO clients having trouble accessing Exchange over VPN now. New thoughts?
tcianfloneAuthor Commented:
I am closing this question here and reopening it new with a different slant. It is now plain that ALL my remote clients are experiencing this problem, so it is no longer an Outlook problem but an Exchange/Win2003 Server/Networking problem. Thanks.

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