Anyone?

This is getting extremely frustrating not being able to find a solution to this.  I posted in a different forum; however, only get one reply (that didn't help) and then nobody else.

Again, this affects everyone - it is not isolated to a few
It affects both Windows 7 and Windows 8.1 using Outlook 2010 or Outlook 2013 (via our Exchange 2013 system).
OWA and Mobile phones connected up to Exchange work perfectly.

It has to do with the way Outlook works with web filtering proxies (Cisco IronPort in our case).
I know this, because if I bypass our proxy (I have a static IP that I use to set up some of our HP Servers), then Outlook works perfectly.  Now, we do not enter in any credentials for our proxy, no settings get entered into IE via GPO or manually. - it just picks up the LDAP from AD (2008 R2 here).

I've tried all of the following:

Even though it's not isolated:

1. I've repaired my Outlook install
2. Created a new Outlook profile
3. Cleared the Outlook Secure Temp file cache (well it was empty anyway)
4. Tried disabling the trust center "don't download pictures automatically" option
5. Went away from cached mode
6. Removed our AV (from my system...it's Kaspersky)
7. Verified registry is pointing to the correct SecureTemp folder
8. Reset all IE settings back to default

For a more proxy targeted approach, I set the AllowImageProxyAuth DWORD in Outlook and it did not help either.
https://support.microsoft.com/en-us/kb/2846350

There is nothing in IronPort blocking the site and we have still entered in bypasses; yet, images still not showing.

Does ANYBODY have any ideas?

I see someone replied; however, realized that I had already tried that (verifying the Cache value in the registry).

Nobody else has ever run into an issue like this?

Hi,

Based on your description, I suspect that your proxy is in internet zone by default, so it cannot use credential which has been recorded in window credential management. I suggest that we add proxy server into Local Intranet zone via GPO to see if it can solve your problem.

Let me know if it works for you. Thank you.

Hi Chloe,

Thanks for the idea, I hadn't thought of it.

However, it does not seem to be helping me.  I did not add it in via GPO, for testing I only added it in to my IE settings.  I also tried "Trusted Sites" without any luck.

FOUND IT

Turns out that Cisco released a bug in one of their updates to their IronPort system.  This bug identifies emails with web content as webmail.  Since our company blocks webmail (gmail, yahoo, etc...) it got blocked. 

• Marked as answer by wrecked.admin 17 hours 17 minutes ago