Mifi 7730L doesn't get along with Microsoft Office Online

[jeffro2]

I've got a user with a Mifi 7730L who for some time has had a variety of problems with her Office 365 Sharepoint/Office Online, Outlook, and Skype for Business.

She mentioned in passing that her Outlook 2016 and Skype take about 10 minutes to connect after she called to report that opening a spreadsheet saved to her Sharepoint-based Microsoft Planner in desktop Excel would freeze with Excel at the splash screen with the message "contacting server". As we discussed this and some unrelated issues, after about 10 minutes, the spreadsheet finally opened.

Interestingly, and why I think the problem is with the Mifi 7730L, is that when she makes a VPN connection to the headquarters office, Outlook and Skype connect immediately, and opening the spreadsheet from planner happens in about 10 seconds, not ten minutes. She told me she typically connects the VPN first before opening Outlook and then afterwards drops the VPN connection and Outlook continues to work.

I also identified that when running the Outlook Support and Recovery Assistant it took an unusually long time to complete the initial authentication-related steps after the user signed in.

I preemptively disabled IPv6 on the user's laptop and rebooted. The Mifi 7730L also has IPv6 disabled. Is there anything we can do to get the Mifi 7730L and Office 365 to work together smoothly? Should she call Verizon tech support to resolve this?

[John_Getzke · Accepted solution]

It sounds like something with that users MS Office configuration is getting blocked by Verizons NAT firewall profile.  Once the VPN is engaged then the firewall is not an issue and the traffic is allowed to reach its destination.

I'll save you a call to Verizon and confirm that Verizon is not going to make customizations to their NAT firewall configuration for your user or organization.  Were all in the same boat and the current well known and documented work around if you don't like it is to use a VPN, which you are already doing.

Your best chance at a solution is to take a deeper look at the users MS Office traffic.  Isolate with network monitoring tools what kinds of calls are going out and getting blocked or timing out when the VPN is not engaged.  MS office products do a lot of goofy lookups when they are launched including talking to printers, checking files for known viruses and other misc network lookups.  Any number of things could be causing the problem.

For example, I've resolved an issue with Verizon and MS Office where office network printers were causing delays in saving changes to MS Office documents.  This problem only became an issue over Verizon 4G LTE, normal broadband connections were fine.  The solution was to change the default printer to a local printer (adobe PDF, XPS Writer, any USB printer, etc) instead of the network printer the users normally use at their desk.

[jeffro2]

Thanks for the info, John. I really appreciate your response. We have employees all over the place with a variety of Internet connections and Outlook timeouts and connectivity problems feature occasionally with other carriers as well.