Those who continue to play Epic Games' Gears of War on the PC have run into an unfortunate problem. It appears the game refuses to start, something being reported on Epic's forums and on various gaming news sites like Voodoo Extreme. The issue was addressed in the linked forum thread by an Epic employee, saying the studio is aware of the problem and currently working on a fix with Microsoft.

After seeing the post we loaded up our version of the game and found the same error which read 'You cannot run the game with modified executable code. Please reinstall the game.' Users were reporting a reinstall does not address the issue.

As suggested on the Epic forums, we then tested out the proposed solution of winding back our system's clock. We set it at January 22, 2009, relaunched the game and were successful in getting it up and running. Until Epic finds a solution, it appears this method will have to suffice.

We've put in a request for comment to Epic but as of yet have not received a response.

Gear of War was released for the PC in November of 2007, approximately one year after the Xbox 360 version.

http://uk.pc.ign.com/articles/949/949500p1.html