I've got a message to GOG already sent, but I wanted to still pose this question.
I can't get the game to launch. I get the following message dialog that pops up in a box when I try to launch:
"Patrician 3: The resolution (800x600x16) could not be initialised. Please install the latest driver for your video card and then start the "P2Setup.exe" program."
I admit I haven't tried to update the graphic card driver, primarily because the game is older than the card. I also had run the test box repeatedly and tried to set the resolution to the max, but I still get this dialog box no matter what I do. Once you click "OK" the box closes and that's all that happens. It's very frustrating.
I can find no other setup options or other things I can change.
Thanks for any ideas.

I haven't had any problems with the support team at GOG. Peter (hello dude!!!) answered my questions as best as he could when I presented him with a DXDIAG that featured Win7 as the OS. The support guys are human just like the rest of us AND they are providing the best support they possibly can for games that they had absolutely nothing to do with other than removing their resident DRM and making sure that they run on the modern OSes. I live in the US and I fully expect to wait a while for an answer considering that my question most likely goes all the way to Poland. (Boze kochany, dlaczego ludzie nie moga czekac pare dni na odpowiedz, eh? Ja pamietam kiedy nie bylo Internetu tak jak teraz jest!!!)

We need to keep abreast of the times... unfortunately. ;)

Thanks GOG works like a treat, basically I'd already gone through the Graphic Card test "P3Setup.exe" and just said for each resolution that it worked (even though it didn't) before I noticed your registry fix which is a quicker way to achieve the same result. I wonder for how many people "P3Setup.exe" doesn't actually work properly for. Strangely for Patrician 2 that graphic card test worked ok for me even though there should be little difference between the two games.

Thanks for the registry fix. I have a widescreen monitor and windows xp 32bit and now it works fine.

Kindest Regards
Torti

Me to I unpacked the registy file that GOG offered but it did not seem to work. Is there something I am missing

This game really REALLY doesn't like the Windows DEP security feature.
Rather than turn it off entirely, you can disable it just for the game.

Right-click
"Computer" or "My Computer", and choose "Properties"
On Vista or Windows 7, choose "Advanced System Settings" form the left.
Select the "Advanced" tab.
Under "Performance", click the [Settings] button.
Choose the "Data Execution Protection" tab.
Select "Turn on DEP for all..."
Click the [Add] button.
Navigate to the Patrician 3 folder (c:\program files (x86)\GOG.com\Patrician 3 or something like that by default)
Add at least Patrician3.exe and P3Setup.exe (I also added P3HardwareSettings.exe and binkplay.exe to the exception list, just to be sure)

TADA! A working install of Patrician 3, without completely disabling DEP!

The .reg file didn't work for me directly. I tried all solutions on this page. Finally this worked:

I used the reg file.
Turned off DEP for the files indicated in the above post.
And then went through the whole list of resolutions from the display setup, clicking that they did display correctly although none did.

Worked after all of these things. In that order. Running Win7.

I still skipped step 2 and it worked for me. So maybe others could get by just doing step 3? Say yes even if the picture doesn't show up. Maybe that's all that's needed. (Win7 64 bit)

Ok, as I am not techiie, can someone please translate the solution to a non computer freak? I have no idea what the solution means and how the bug is solved. And please explain for dummies.

I had the same issue (using Win XP 32 bit): "The application failed to initialize properly (0xc00000005). Click on OK to terminate the application." (By the way, I'm getting the error message twice. Strange.) The registry fix didn't help and neither did adding Patrician3.exe to the exception list for DEP.

But! Turning off DEP for everything but essential Windows programs and services DID the trick and the game loaded up!

The only downside is that this requires a reboot and I don't really feel like permanently turning off DEP, so it takes a little more time to load the game but after the dissappointment of Patrician IV, I really wanted to be able to play the third installment :)

EDIT: And now I realized that this thread was three years old... Oh well.

Actually, I was partially wrong about the above post! I had an older installation of the game from the old CD version I had and made the DEP exception for that .exe by accident. After adding a similar exception for the proper .exe, it now seems to work at last :)