Multiple Remote Employees w/ AT&T Suddenly Having VPN Issues

Title says it all. We have a few remote employees with AT&T and the router they supply. As of last week, these employees can not access the GlobalProtect portal on their home networks. Our remote assistance tool (Remote Utilities) is also blocked. Teamviewer was the only thing that worked.

Things I’ve tried:
Disabling IPV6 (saw on a forum somewhere that this was an issue)
Creating app/port exemptions AND enabling DMZPlus mode for the company laptop on the router’s firewall (I rolled these changes back after it did not work)
Setting Remote Utilities’ port to match Teamviewer’s

Update: It was DNS… AT&T’s DNS servers didn’t recognize our domain, but worked otherwise. Changed the network adapters to use Google/Cloudflare DNS and that resolved our problems.

Sounds like ATT. But they will swear nothing has changed.

Do you have a technically savvy user who can put the ATT device in bridge mode and use a decent home router instead?

also, be aware that some have seen lag time in making changes and those changes actually working.

We’ve seen users connecting to AT&T home services have settings in their NIC’s changed. I would inspect their NIC settings and compare to a non-affected user.

Try setting the DNS server on the PC and AT&T router to 8.8.8.8 or 1.1.1.1. Whatever DNS server the AT&T router is using (and probably passing to the PC) may be having issues.

I’ve seen this several times when deploying PCs in other countries. The default DNS servers for their home ISP struggled with either the TeamViewer or Splashtop sites/services. Using a well known DNS like 8.8.8.8 or 1.1.1.1 immediately fixed the issue.

Sorry, it seems this comment or thread has violated a sub-reddit rule and has been removed by a moderator.

Your account must be 24 hours old in order to post.

Please wait until your account is a day old, and then post again.

If your post is vitally time sensitive, then you can contact the mod team for manual approval.

If you wish to appeal this action please don’t hesitate to message the moderation team.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

Unfortunately this has happened to 3 users, and it just started last Friday. We don’t have too many employees working from home, but I believe this is every single one of them with AT&T.

Jumping from their personal hotspot (once connected to VPN) over to their home internet seems to work, as long as they don’t disconnect from the VPN before switching.

When you say NIC settings changing, do you know if there’s something specific on their home router I should be checking for?

Forgot to reply to this, but changing the DNS servers on the network adapter fixed it. These users were all local, so AT&T must have broken their DNS.

Thanks!

The settings were changing in the NIC’s of their laptops. From memory, I want to say it was in the advanced TCP/IP settings of the NIC itself. Compare an affected users settings (check boxes, etc.) to a non-affected users settings.

We did not touch their personal routers.