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Game developers who use popular tool GameMaker Studio have been advised to make a back-up copy of any projects, immediately. A recent update to the system has included a bug, which triggered the game's unusual anti-piracy system, permanently ruining many games-in-progress.
The anti-piracy system is quite clever, when it's working correctly. Developers who are using an illegally acquired version of the software find game resources - including character sprites - replaced with an image of a skull and crossbones, the international sign for piracy. Those resources are permanently edited, and unable to be restored.
Obviously this is an impressive deterrent for people considering pirating a copy of GameMaker Studio, but what happens when the gremlins get into the machine and people using legitimate, purchased copies of the hardware are also affected?
Please don't ASSUME folk are using pirated copies, sometimes a virus or something can effect an exe and gives some issue like this.
The current solution is to uninstall, delete both %appdata%\GameMaker-Studio and %localappdata%\GameMaker-Studio, delete the GameMaker-Studio registry key, scan your machine in case its a virus, and then reinstall.
The program assumes a modded .exe is a crack, but this isn't always the case as a virus can also change it. I also have a feeling theres something else changing exe's.....
That's the closest we have to an official fix, but rest assured the developers are well aware of the problems, and are working to tidy up all issues relating to GameMaker Studio.
UPDATE: It is now safe to return to your game development! A spokesperson for GameMaker Studio has reassured us that the errors have all been fixed, and the rogue DRM appropriately squished. Thank goodness.