What can cause an exe to not launch, with no error message?

[bizzybody]

XP Pro SP3, all current updates.

I have some exe files that for reasons unknown, XP is not allowing to run. One is xflash_utility.exe from codeguys.rpc1.org a utility for flashing LiteOn optical drives with firmware.

The others are the JIT version of the Basilisk II 68K Macintosh emulator and the SheepShaver PPC Macintosh emulator.

When I doubleclick or rightclick then click Open, nothing happens. THERE IS NO ERROR MESSAGE. The name of the exe will briefly flash in the process list in Task Manager. I'm logged in as a user with Administrator rights. I've also tried run as Administrator and logged in as Administrator.

Other exe files run without a problem. The emulators were running fine but suddenly they will not, just happened yesterday.

It's not Avast antivirus causing the problem. I've stopped it and even killed it, those programs still won't run. The optical drive flasher never has been able to run on this particular PC since I downloaded it. The program is OK because it will run, extracted from the same ZIP file, on another PC running XP Pro SP3.

I have run into XP completely refusing to allow certain exe files to be launched before this and the only cure I could find was to do a clean install. I just did a clean install not long ago and I am not going to do it just to get three little programs to work, especially not when two of them would run two days ago.

[WatchSmart]

You know, both SheepShaver and Basilisk II have this quirk where if the path to your hard disk image is wrong (or something else is wrong in the config, perhaps) the emulator just fails like you described. Running the .exe does nothing and no error is given.

Maybe try deleting your config files and setting it all up again in the GUI.

Edited September 7, 2009 by WatchSmart

[bizzybody]

Did that, several times.

Tonight I booted up with DaRT 5.0, deleted the swap and hibernation files then used its system restore to roll back a couple of weeks. Rebooted and the emulators now run.

Microsoft Update has nothing "new", so it can't have been a "security" update that decided the JIT mac emulators are malware.

But the Xflash program from codeguys is still being blocked from running.

[Tripredacus]

Some malware create hidden blocking keys in the registry that stop programs from opening. Scan for rootkits if you can. This is especially a concern if the programs that can't open are utility programs, but not things like games or productivity software, or things like Calc or Solitaire.