The issue has been coming up since updating my servers a few weeks ago. After the update they started fine and I did some config work on one of them and restarted it successfully to test the config (installing some sourcemod plugins, basically). The next day when I resumed work on the server (I'm setting it up for a LAN party), it refused to start successfully; and I discovered the other three - one of which includes an all-stock failsafe that's not been modified at all - were encountering the same issue.

I am reasonably sure that it's an error with the TF2 server software somehow; I've not only done a clean server install (separate from the previously mentioned all stock server) both on my desktop - which is where the issue first cropped up - and my laptop, and I've encountered the same issue. As both run Windows 8, I've also decided to run an old Windows 7 installation that's not had any software updates in several months (since before SteamCMD was rolled out) and did a clean server install there, as well as tested the previous servers, with the same issue. I've run some diagnostics on both computers (as in, pretty much every test I could think of. It took days) and the hardware on both seems to be running perfectly. Additionally, to eliminate the possibility that my home router is causing any issues, I've tested the server on my laptop running over tether (which has worked previously) and on some other connections and I'm encountering the same error.

I've done some looking on Google, but this seems to be an issue that's normally encountered on Linux systems; or at least, that's what I'm finding when I search for that specific error on Google.

Any ideas? It's weird that I seem to be the only one having this issue on Windows, but I can't seem to find anything else to look for on my end.

EDIT: No changes on my end, but my desktop is now successfully starting all four servers. Laptop is still encountering the error. Still no idea why this happened in the first place, but hopefully it won't happen again (and sorry people from Google - I can't give any advice. I honestly don't know what happened here)