Hello,
I have 7 users that are experiencing a loss of connectivity to the O365 exchange server in their Outlook 2010 clients.
The users are also unable to access their mailboxes through the web portal. (They are able to auth. into the portal, but they experience a time-out when trying to access their inboxes).
This is browser agnostic (seen across IE/Chrome/Firefox) and there are users on-site that are able to successfully connect.
The users are able to access their respective server(s) outside of our internal network. There is a firewall in place that is most likely causing the issue. (Sonicwall TZ-200)
Taken troubleshooting steps:
- Added all Office 365 (Portal/Online Svcs/Exchange Online) IP Ranges as incoming exclusions on the following ports:
- TCP 25
- TCP 80
- TCP 443
- TCP 587
- TCP 995
- Confirmed that the issue is not present at a secondary office site with the same Firewall and Configuration.
- Deleted/Re-attached O365 email accounts to profiles before and after running O365 desktop configuration again
- Confirmed O365 sign-in assistant install updated
Connections were inturrupted last week for three days (WED-FRI), they were all active and operational Monday of this week, but are now inactive once more.
Noticed a forum thread that cited a possible authentication problem once the user attempted to be validated after attempting to access their exchange server via O365 portal. (may be helpful)
MSFT RCA (RPC/HTTP Connectivity):
Image may be NSFW.
Clik here to view.
I've talked with O365 TS over the last 72 hours and have been only able to identify the above. No solutions have
Thanks, -RJ
