Apex Legends is no stranger to technical issues of all sorts, but it seems the recent invalid game executable error is more pervasive than we've been used to. Namely, the r5apex.exe error makes you unable to run the game, which is obviously a major problem.
Here, we'll try to explain what this particular error does and what some potential fixes might be. Having said that, there is some conflicting info available online, so be sure to take all of this with a grain of salt. Can't hurt to try, however.
How to Fix Apex Legends Invalid Game Executable Error?
Those who have a bit of technical know-how will have already realised that the r5apex.exe file is Apex Legends' main executable - the file that you use to start the game. If this particular executable gets corrupted, the game won't run, but thankfully there are relatively easy ways of solving this.
According to what information we've found, Avast Antivirus seems to be getting a false positive when scanning the Apex Legends installation. This means it quarantines the executable in question, essentially getting rid of it entirely. Reinstalling the game won't do anything in this situation, as Avast will automatically quarantine the newly-copied executable, too.
If this is the case on your end, open Avast, go to the 'Protection' menu, and then check the right-side corner of the Avast interface. When you finally find your r5apex.exe, just unblock it via Avast, and you'll be good to go. That said, you may have to repair your installation of Apex Legends via Origin after unblocking the executable. This should resolve all the problems you might have.
We hope this guide helps you in getting Apex to run again. If it does, check out our Voidwalker event patch notes, as well as our huge list of best free games on PC, where Apex is coincidentally one of our favourites.