FSUIPC access violation

[huppel]

Hi,

Today I suddenly got the "Flight Simulator has detected a a problem with a third-party .... module FSUIPC4.dll version 4.859n" message with the choice to run FSUIPC or not. If I choose to run it FSX crashed soon after...

Strange thing is, yesterday everything run fine and today suddenly on first startup of FSX this problem appeared.

I searched already through the forum and saw that I'm not the first one suffering from this so I already tried a few thing. I'll try to give you an overview of my system, the exact error message and log file and what I've already tried.

System:

Intel I5-3570K

16 Gb of memory

MSI GTC 670 videocard driver version 310.90

Windows 8 64 bit

FSX Acceleration

FSUIPC4 (Registered) version 4.859n (as you can read below the problem started today running version 4.853)

Error messages:

- First the above described "FSX detected a problem with FSUIPC do you want run this software" -> click yes

- second "fatal error" reported and FSX stops working

- in the windows event logger:

Faulting application name: fsx.exe, version: 10.0.61637.0, time stamp: 0x46fadb14

Faulting module name: FSUIPC4.dll, version: 4.8.5.9, time stamp: 0x50f440c1

Exception code: 0xc0000005

Fault offset: 0x0001c2a4

Faulting process id: 0x6b0

Faulting application start time: 0x01cdf36847f8c16c

Faulting application path: C:\Games\FSX\fsx.exe

Faulting module path: C:\Games\FSX\Modules\FSUIPC4.dll

Report Id: 96e69215-5f5b-11e2-bf33-3085a98e3a1c

Faulting package full name:

Faulting package-relative application ID:

What I've tried:

The problem strarted today running FSUIPC V4.853

First I deleted my fsuipc ini file, did did not help.

Then I reduced my dll.xml and set the only exe in exe.xml to disabled and removed all trusted modules (except the default FSX) from fsx.cfg

dll.xml:

<?xml version="1.0" encoding="Windows-1252"?>

<SimBase.Document Type="Launch" version="1,0">

<Descr>Launch</Descr>

<Filename>dll.xml</Filename>

<Disabled>False</Disabled>

<Launch.ManualLoad>False</Launch.ManualLoad>

<Launch.Addon>

<Name>FSUIPC 4</Name>

<Disabled>False</Disabled>

<Path>Modules\FSUIPC4.dll</Path>

</Launch.Addon>

</SimBase.Document>

exe.xml:

<?xml version="1.0" encoding="windows-1252"?>

<SimBase.Document Type="Launch" version="1,0">

<Descr>Launch</Descr>

<Filename>exe.xml</Filename>

<Disabled>False</Disabled>

<Launch.ManualLoad>False</Launch.ManualLoad>

<Launch.Addon>

<Name>Couatl</Name>

<Disabled>True</Disabled>

<ManualLoad>False</ManualLoad>

<Path>fsdreamteam\couatl\couatl.exe</Path>

</Launch.Addon>

</SimBase.Document>

As this did not solve my problem (funny thing is the trusted line about fsuipc is added automagically to fsx.cfg without me having to approve the module) I installed the latest version of FSUIPC and removed the trusted line again.

If I'm right now I needed to trust the module but it did not solve my problem.

After reading some more about the problem in the forum I enabled the simconnect logging but it does not provide any usefull information to me:

0.00000 SimConnect version 10.0.61259.0

0.00212 Server: Scope=local, Protocol=Pipe, Name=\\.\pipe\Microsoft Flight Simulator\SimConnect, MaxClients=64

0.00367 Server: Scope=local, Protocol=IPv6, Address=::1, Port=50593, MaxClients=64

0.00438 Server: Scope=local, Protocol=IPv4, Address=127.0.0.1, Port=50594, MaxClients=64

562.24939 Panels data export found and set to 20B319D8

Unfortunately no FSUIPC log file is created, I think it does not get that far...

I've got no clue what to do any more perhaps you can give me a hint.

Best Regards,

Marcel Fransen

[Pete Dowson]

I searched already through the forum and saw that I'm not the first one suffering from this

Actually, yes, you are the first to ever report an Access Violation problem during start-up. None of the others are access violations, or at least none that were reported with sufficiant information.

Exception code: 0xc0000005

Fault offset: 0x0001c2a4

Unfortunately no FSUIPC log file is created, I think it does not get that far...

I've got no clue what to do any more perhaps you can give me a hint.

This is all very useful information and will help me immensely to work out what is wrong. Interesting that you made it start with a default INI file too -- the INI file is processed before the Logging is started, and it would otherwise be possible that some mangled entry is the culprit. You've already eliminated that as a possibility.

It's getting late here now but I'll look at this first thing in the morning.

Regards

Pete

[Pete Dowson]

It's getting late here now but I'll look at this first thing in the morning.

I couldn't resist having a quick look before retiring.

The access violation offset points to the FSUIPC4 entry point! None of my code has been executed yet! Ouch!

I've made a re-compiled copy with slightly different compilation options. Could you try it please, and let me know?

fsuipc4859nTEST.zip

Thanks,

Pete

[huppel]

Hi Pete,

Thanks for the quick reply, I'll try it tonight as I get home and report the results. On the other hand as I read where it crashes I think there is a rather big change that it is not caused by FSUIPC but that is just the one that gets corrupted. As mentioned I did not make any consious changes to my system between the working and crashing situation but perhaps something caused FSX to get in an invallid state (altough it still starts up correctly if FSUIPC is disabled, but then again that is the problem with AV's change somtehing and memory corruption might no longer be detected...)

Best, Marcel

[huppel]

Hi Pete,

Unfortunately the dll you provided does not make any difference. I checked all the files in FSX and the %appdata%\Roaming\Microsoft\FSX folders to see if unexpected files were recently changed to no avail.

I also checked the wintrust reg settings but that was okay. I could find one person explaining he got into a similar situation when he switched to another application when FSX was loading. I don't knoe how serious this post is but I must admit that I did that when the problems started (but I did that more often before without getting into trouble). Unfortunately the post did not mention how to fix the situation.

Best Marcel

Edited January 17, 2013 by huppel

[huppel]

Good news!! I got it to work again! For everyone ever facing the same problem (only if you are an experienced windows user, don't blame me if things get worse):

1) start regedit

2) goto key HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers

3) delete the key "C:\\Games\\FSX\\fsx.exe"="$~ RUNASADMIN IgnoreFreeLibrary<FSUIPC4.dll>"

4) if you would like to run FSX as an administrator you need to activate that again as you removed that in step 3

Everything should be ok now!

Some background: As I could almost rule out file changes (because I did not change anything and I could not find a changed file) my best bet was that it was something in the registry. So I searched for FSUIPC in the registry and found the interesting "IgnoreFreeLibrary<FSUIPC4.dll>" part of this key. As I had nothing to loose I deleted the key (after exporting it so I could go back when needed). And that solved the problem!

Now of course it is intesting to know how this key was created. What the key means I could find here: http://technet.microsoft.com/en-us/library/cc722047%28v=ws.10%29.aspx

It means that freelibrary calls are ignored (calls used to unload a DLL, known as module in FSX). This probably means that one of those calls somehow failed once and the key was added by the MS compatibility 'service' as a service to you...

I tend to believe that indeed task switching while FSX was loading played a role in this but I will probably never know...

I'm just very happy as this saves me a lot of time (I was about to reinstall FSX but that probably would not have helped as the reg key would still be there).

Pete, thanks very much for the version you created especially for me late at night, much appreciated!!! If I hadn't already registered for FSUIPC I would have done that right now (for anyone in doubt: I doubted first too but I'm in love now with the extended controller programming and profile support!!).

Best Marcel

[Pete Dowson]

Some background: As I could almost rule out file changes (because I did not change anything and I could not find a changed file) my best bet was that it was something in the registry. So I searched for FSUIPC in the registry and found the interesting "IgnoreFreeLibrary<FSUIPC4.dll>" part of this key. As I had nothing to loose I deleted the key (after exporting it so I could go back when needed). And that solved the problem!

Now of course it is intesting to know how this key was created. What the key means I could find here: http://technet.micro...7(v=ws.10).aspx

It means that freelibrary calls are ignored (calls used to unload a DLL, known as module in FSX). This probably means that one of those calls somehow failed once and the key was added by the MS compatibility 'service' as a service to you...

Well, I am amazed! Great detective work on your part! It seems incredible how "helpful" Windows is (NOT!).

Thank's for explaining it so clearly. I think I shall add this snippet to one of the FAQ's already in the FAQ aubforum. Or, actually, it would really be better coming from it's discoverer. Could you do that, please? Think of a suitable title and post your solution to the FAQ subforum? I will then make sure it is pinned.

Thank you!

Pete

[huppel]

That would be no problem, I will do that this evening when I get home.

What I'm still not sure about is if this is windows8 specific. But as it seems that not a lot of people hit this before I tend to think it is...

Best, Marcel

[huppel]

Done!

Thanks again for your help!

Marcel