remove user mods and repair DCS does not start anymore

[TheBiggerBass]

Started DCS a few hours ago without isssues. Without any changes or updates since last succesful start of DCS today, DCS suddenly fails to start now with this error message (full dcs.log attached):

2025-11-05 22:52:47.894 ERROR   ASYNCNET (Main): HTTP request dcs:logout failed with error 99: Unrecoverable error in select/poll
2025-11-05 22:52:47.894 ERROR   ASYNCNET (Main): Logout failed: -99
=== Log closed.

DCS launcher starts but DCSstops with the error message above.

How to fix that?

dcs.log

[razo+r]

Have you made any changes to your mods before it stopped working?

Have you already tried removing all mods, run a repair and see if that fixes your issue?

If not, try renaming your saved games folder.

If yes, add one mod after another to see which one causes issues.

[rob10]

Wow, you've got a lot of mods installed and it appears you're getting bunch of errors on them.  I'd start with removing them, if only reduce the clutter in the log.

[TheBiggerBass]

vor 5 Minuten schrieb razo+r:

Have you made any changes to your mods before it stopped working?

Have you already tried removing all mods, run a repair and see if that fixes your issue?

If not, try renaming your saved games folder.

If yes, add one mod after another to see which one causes issues.

vor 6 Minuten schrieb rob10:

Wow, you've got a lot of mods installed and it appears you're getting bunch of errors on them.  I'd start with removing them, if only reduce the clutter in the log.

Well, this morning DCS started as usual. Without applying any other changes it does not start anymore now. I wonder what has changed.

[rob10]

Something got changed in a file somewhere (DCS or even in Windows).  Some part in your computer finally started failing or failed just enough that it can't keep up any longer.  Who knows.  Regardless, with that many mods (or really with any), the most prudent 1st step in troubleshooting is remove them all and do a repair on your DCS.  It's really not worth spending a lot of time troubleshooting until you do that.

Edited 15 hours ago by rob10

[TheBiggerBass]

Ok, starting with a new Saved Games/DCS folder fixed started DCS.

However, I did not change a single file or setting since this morning and DCS does not start anymore. Something external must have changed.

[sleighzy]

Same log error in logs as user who reported game wouldn't start for them earlier today. Removed their mods and worked. Not sure if anything related between these two re: common mods.

 

[silverdevil]

11 hours ago, TheBiggerBass said:

2025-11-05 22:52:47.894 ERROR   ASYNCNET (Main): HTTP request dcs:logout failed with error 99: Unrecoverable error in select/poll
2025-11-05 22:52:47.894 ERROR   ASYNCNET (Main): Logout failed: -99

there is another post commented on by @sleighzy

turns out mods all or in part fixed the issue. the line in your log seems to be a network error.

"error 99: Unrecoverable error in select/poll: This is the core of the problem. "select/poll" are system calls used by applications to monitor multiple file descriptors (including network sockets) for activity. An "unrecoverable error" in this context suggests a fundamental issue with the operating system's ability to manage network connections, potentially indicating a problem with network drivers, firewall configurations, or VPN software."

[TheBiggerBass]

vor 33 Minuten schrieb silverdevil:

there is another post commented on by @sleighzy

turns out mods all or in part fixed the issue. the line in your log seems to be a network error.

"error 99: Unrecoverable error in select/poll: This is the core of the problem. "select/poll" are system calls used by applications to monitor multiple file descriptors (including network sockets) for activity. An "unrecoverable error" in this context suggests a fundamental issue with the operating system's ability to manage network connections, potentially indicating a problem with network drivers, firewall configurations, or VPN software."

Well, although this error seems like the same, I guess the situation is different for me.

1st of all a recreation of Saved Games/DCS from scratch fixed it for me but not for @H60MTI

I don't use any VPNs and my network is working with all other applications without any issues. As a recreation of Saved Games/DCS fixed it the error can't be located within my network setup.

I am just guessing now but it seems there was kind of a file marker created from last login before which had not been deleted after logout. DCS seems to read this file marker as an indicator it is still logged in and therefore logout failed. I don't know if this makes sense but the error message might suggest that.

Atm I am adding the mods back to Saved Games/DCS only as needed but I still wonder why my previous configuration with all mods active did work for weeks without issues.

 

[sleighzy]

5 minutes ago, TheBiggerBass said:

1st of all a recreation of Saved Games/DCS from scratch fixed it for me but not for @H60MTI

Recreating their Saved Games\DCS folder did actually fix it for them  

Yes, there is some auth data there. They were able to identify a specific mod causing issues as they added them back in one by one. 

[TheBiggerBass]

vor 1 Minute schrieb sleighzy:

Recreating their Saved Games\DCS folder did actually fix it for them  

Yes, there is some auth data there. They were able to identify a specific mod causing issues as they added them back in one by one. 

That sounds plausible to me. I'll check which mod could be suspect causing the error.

[sleighzy]

20 minutes ago, TheBiggerBass said:

That sounds plausible to me. I'll check which mod could be suspect causing the error.

Sounds good. They didn’t supply a followup log for the mod with the issue so hard to say if they got the exact same error again. If you find you have an issue when you start adding them back in again drop a note with the one in question and another log. If no issues then yeah may just be something else cached there that I mentioned (or gremlins). 

[TheBiggerBass]

Must be Gremlins. It can't be something else