Hey all. So I’ve spent the past couple of days trying to troubleshoot what exactly is wrong with my internet where it keeps connecting and then disconnecting to the point where I went the nuclear route and completely reinstalled Windows. I thought it was a Windows registry error, but long story short, it turns out the issue is due to Plex Media Server.
What happens is when PMS is opened (I have it open when Windows is turned on), that specific device goes into a cycle where it will lose internet connection for a short period of time (probably around a couple of minutes), and then regain internet connectivity for a period of time (also usually for a couple of minutes). No other devices connected on my network is affected (including devices that are using Plex to watch streamed content off that server), and even while the PMS host computer is in the “down” part of the cycle, I can ping my router, so it’s not as if the issue is related to hardware. The second I close PMS, the internet will go right back to normal after around 30 seconds and no cycle will happen again.
This behavior can be replicated on two separate devices (one a 5ish year old laptop, the other a recently built desktop), so I know something is definitely up with the latest PMS version and either my router or Windows 11. I’ve come to ask any of you how I can get started troubleshooting this as a lot of the articles on the Plex support blog don’t seem to be related to something like this, or if anyone has had something similar happen.
Most likely your router is taking offense from one of Plex’s regular behaviors. Either because of a poor firmware or because of an intended, but misfiring security feature.
See if there are some advanced security features in its “settings” menu, from which you can define exceptions for the Plex server machine.
In the worst case you’ll have to replace the router.
I am having the same issue, also on a Windows 11 machine.
At random times, both the ethernet and wifi will “disconnect,” and although sometimes it will say that both are still connected the connection is essentially dead.
Windows troubleshooters can find nothing wrong. I didn’t go the full “nuclear” route of a clean reinstall of Windows, but instead did a repair install and that didn’t work either. Neither did reinstalling or updating the ethernet drivers…
I was even considering buying a PCI ethernet card thinking that the connections on the motherboard were failing. However, before doing so I did a clean boot and, through a process of elimination, discovered that the problem is Plex Media Server.
Stopping PMS (1.30.0.6406-f3f2fcc0a) from booting with Windows “fixes” the problem, though such a “solution” is obviously not ideal since it means not running PMS. I’ve tried uninstalling and reinstalling Plex, and even tried rolling back two versions, with no success either. I am not sure whether something is “left behind” after uninstalling PMS that an older version doesn’t change or if this is a problem with the two preceding versions that I hadn’t noticed.
It would be strange if the problem wasn’t with PMS and the OP and myself are coincidentally having the same issue with our modems at the same time, though I guess it’s possible.
Whatever the case, I hope someone can figure out what might be the issue.
I figured out this happens because FiOS Home Network Protection recently pushed an update to its definition file blocking Plex Media Server. You can solve this by simply turning off the Home Internet Protection software (through the myFios mobile app).
For whatever reason, blocking internet access to the affected device and then turning it back on also works on the router settings page, but the problem will come back after you restart your computer or connect to a VPN. Best solution for now is to just turn off FiOS Home Network Protection.
I have CenturyLink and the same thing has been happening to me this past week or so. It doesn’t matter which machine I have Plex Server installed on, it just kills my internet. Very frustrated at this moment as we haven’t been able to watch any of our movies lately and with the holiday’s coming up a fix is needed. Nothin has changed with my ISP. There is no new updates or protection software.
I am glad OP found the issue with their connection. I also have CenturyLink, however, so the Fios fix won’t work for me, though perhaps it could point a way to what may be causing the issue for others. I wonder if there’s been a change in how PMS communicates with the server and if this is triggering a security response.
I may have figured it out and it is a similar situation to the original poster.
If you go into the settings for your modem, CenturyLink includes a “cyber security” function in the advanced settings of the modem, something which I had not ever noticed before.
From what I have been reading, it seems to be a basic firewall run off of McAfee software. After reading other unrelated forums in which people complained about how this setting blocked functionality of various programs that require the ability to communicate outside the home network (things like email and dns servers) and how this problem was solved by turning this function off, I have been running a trial of having it off. Since then, I have not run into any issues with Plex and internet connectivity.
I’m guessing that either, like the OP, a new definition was pushed out and blocked Plex or, equally plausible, a new definition is needed due to a change in Plex and it’s not coming from CenturyLink (esp. given their general lack of hardware support and the ongoing changeover in ownership).
There doesn’t seem to be any way to force an update or change the definitions that I can see, and thus the two options are to have it on or off. Provided you are running firewall software on your devices, I don’t imagine the risk is incredibly high for normal users to turn this function off, but of course it’s up to you.
