My wife went into the GAMEDATA/PCBANKS folder and noticed that there are older.PAK files in the folder. Deleting any that are older than today has fixed the issue for both of us. Good luck.

It seems it works, now the game is at the "Stars loading Screen", thanks.:)

Nice tip. TY. Odd their install leaves old crud it is not compatible with.

Downloaded the update, but i don't think i have old .pak files ( http://imgur.com/a/cm9TK ) as far as a i know, and it still won't launch..

Did this, and deleted the shader folder. Still crashes at game mode select screen.

Same happens here. A .. "fulllog.txt" turned up in the gamedata folder. Stops at the second entry after an auth-server url.

So maybe the game just doesn't come as far as to loading any resources.

While the rollback is downloading anyway... You know, once upon a time, in the "good old days", we had "piracy" to fix this kind of thing. We'd have groups that packaged the first stable release, after the worst "gold version woo" had settled. Or, we'd use the first version if there was too much wank going on. And then we'd use that in place of "Hi, valued customer! Just type in your serial-key while you're off-line, and get booted off the game with no error-message. And also remember to physically unplug your cd-writer from the system-bus, and uninstall all your mastering software. Thank you for your purchase! Also, please wait while I install this game from the dvd at 1x reading speeds, thanks to how the copy-protection disagrees with the utterly cheap disc-production we chose in order to save approximately 10 dollars per region!".

And now, with the wonder of the internet, and with everything being digital and technology making everything possible - we get the same old wank back in the rear way.

Actually, screw this, I'm playing something else.

That did it for me. Thanks a lot, mate!

Uninstall and install again actually worked for me. Had to remove all mods to not get hangs, etc., so also betting on incremental updates causing some problems.

Thanks! This did the trick for me.

Original installation: Base 1.0.9.1 (no Mods)
After running new installer (CTD)
Deleted every .PAK file older than the date of the new installation = Success for me.

System time set to before the save file date, will also stop it from loading a save game. If your country has time zones and daylight savings, this might become an issue.

I don't spot any old .pak files in my pcbanks folder, and my game refuses to launch. The green play button in GOG Galaxy depresses itself after a few seconds, and trying to launch with the NMS.exe does nothing. I did try verifying the game files (4 files were downloaded). I've cleared out all mods, I'm not using a trainer and I cleared the shadercache.

Not sure what else I can do. Not keen to redownload the game.

Edit: Uninstalled and redownloaded the game. Still won't launch.

For me the game was not launching at all. Click the launch I found the solution. It's because I am on MacBook Pro in Bootcamp with Radeon R9 M370x. 1.09 works fine but 1.1 is not supported by the latest driver that Apple or AMD provides. I'm guessing its because of specific new graphics features in 1.1 like motion blur etc.

The game worked after I used this solution to "force" Windows to take the latest driver from AMD.

you can find the solution by googling: update-boot-camp-radeon-r9-m370x-driver-on-a-macbook-pro-retina-15-mid-2015-rainbow-six-siege-fix

It's not really a Kosher solution, but I thought I'd share my story in case other players are in my position and don't want to wait until Apple releases new drivers. Follow those instructions at your own risk. (Or buy a damned PC for gaming :-P )