Going to post the fix (what worked for me) here for anyone else with the problem:

1. Log out of social club by going into the GTA 5 folder and running 'GTAVLanguageSelect.exe' as administrator.
2. Log back into social club.
3. Finally, accept any new terms and conditions which was the cause of the problem for me.

Months later still having this problem, anybody else got a fix?

^^^

@Jitnaught said in GTA Startup offline error - Code 201:

Make sure GTA V isn't being blocked by any firewalls you have, such as Windows Firewall.

Thanks for the quick reply.
Just tried that now

yet still getting the same error.

I have just reinstalled GTA (steam) after not having played it in months and as soon as I go to launch I get this error:

I have tried pressing 'Retry' which shows the same error as above and have also tried pressing 'Offline Mode' which gives me this error (I do have an internet connection when starting up):

when pressing 'Retry' on this error, nothing happens and the game no longer appears as 'Running' in steam.

Any help would be great.

@eshenk I have tried both the 'offline mode' and 'retry' button on the launcher and the error 201 still happens, I have now also tried what you have linked but still have the same error. Thanks anyway.

@eshenk Thanks for the reply, still happening after trying this though.

This error happens on both modded and clean versions of GTA (latest version) and happens when loaded through both Steam and RPH, has been happening for about two weeks now and I still don't know why.