Good day all.

Even though I have solved CTD (P3D4 was failing to start) and P3D4.2 is working OK (for now) I'm trying to narrow down the cause. 

I got a lot of help in CTD forum and I am trying to figure if 777 RAASPRO is the culprit. 

Here is my dll file:

<?xml version="1.0" encoding="UTF-8"?>
<SimBase.Document Type="AceXML" version="3,0" id="dll">
    <Descr>AceXML Document</Descr>
    <Filename>dll.xml</Filename>
    <Launch.Addon>
        <Name>PMDG_HUD_interface</Name>
        <Disabled>False</Disabled>
        <Path>PMDG\DLLs\PMDG_HUD_interface.dll</Path>
        <DllStartName>module_init</DllStartName>
        <DllStopName>module_deinit</DllStopName>
    </Launch.Addon>
    <Launch.Addon>
        <Name>RAASPRO</Name>
        <Disabled>False</Disabled>
        <Path>.\RAASPRO\RAASPRO.dll</Path>
        <DllStartName>module_init</DllStartName>
        <DllStopName>module_deinit</DllStopName>
    </Launch.Addon>
    <Launch.Addon>
        <Name>PMDG_Interface</Name>
        <Disabled>False</Disabled>
        <Path>PMDG\DLLs\PMDG_Interface.dll</Path>
        <DllStartName>module_init</DllStartName>
        <DllStopName>module_deinit</DllStopName>
    </Launch.Addon>
</SimBase.Document>

If I remove this part then P3D4 starts without problem:

<Launch.Addon>
        <Name>RAASPRO</Name>
        <Disabled>False</Disabled>
        <Path>.\RAASPRO\RAASPRO.dll</Path>
        <DllStartName>module_init</DllStartName>
        <DllStopName>module_deinit</DllStopName>
</Launch.Addon>

I have only PMDG777 and NG installed in my sim and NG does not have RAASPRO. I also do not have FS2Crew RAAS system installed, never had on this PC. 

I read that other people had issues with RAASPRO. 

I also read that the raaspro.dll was updated. FSCrew has updates in their raaspro forum for the one installed via PMDG aircraft.  PMDG might not have  this file updated.

Thx for looking.   

If your 777 is an up to date version, then the RAAS dll module is also up to date. Check your OC to verify your 777 is current.

There are a lot of people not having a problem with the RAAS module, and the only problems I recall go back to the early days of P3Dv4 coming out in 64b and it took FS2Crew a little while to catch up.

Thanks Dan, I will check on that. 

I just read it on FS2Crew forum that one of the reason could be Office version. I have 64-bit and everything was working fine and when I tried to install Skype for business for some reason my office was reinstalled to 32-bit and it could have triggered an issue. RAAS needs 64 bit version of MS Access Database and even though I reinstalled Office to 64-bit system I may still have old version of MS Access Database.