SOLVED rFactor 2 "Stopped Working" (b798)

Build 798 refuses to work in 64 bit mode. I'm not sure if I am doing something stupid?

When I try and run rf normally (ie 64 bit), I get the splash screen, and then a windows dialog that tells me the rfactor has stopped working.
This does NOT happen when I run in 32bit mode (in other words, when I check the run in 32 bit mode checkbox, rf2 starts up and runs fine)

Sadly, the windows event log is not very helpful...

HTML:

- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
  <Provider Name="Application Error" /> 
  <EventID Qualifiers="0">1000</EventID> 
  <Level>2</Level> 
  <Task>100</Task> 
  <Keywords>0x80000000000000</Keywords> 
  <TimeCreated SystemTime="2014-09-01T08:02:11.000000000Z" /> 
  <EventRecordID>77537</EventRecordID> 
  <Channel>Application</Channel> 
  <Computer>ZACPTMC024.4CIT.local</Computer> 
  <Security /> 
  </System>
- <EventData>
  <Data>rFactor2.exe</Data> 
  <Data>1.7.9.8</Data> 
  <Data>53cd4ca5</Data> 
  <Data>ntdll.dll</Data> 
  <Data>6.3.9600.17031</Data> 
  <Data>530895af</Data> 
  <Data>c00000fd</Data> 
  <Data>000000000003f193</Data> 
  <Data>1a90</Data> 
  <Data>01cfc5bb04c137f1</Data> 
  <Data>C:\Program Files\rFactor2\Bin64\rFactor2.exe</Data> 
  <Data>C:\WINDOWS\SYSTEM32\ntdll.dll</Data> 
  <Data>46ad9024-31ae-11e4-be93-f4b7e2e9e2e4</Data> 
  <Data /> 
  <Data /> 
  </EventData>
  </Event>

I did a full uninstall (and deleted rfactor folders), ad then did a reinstall, I even reinstalled to Program Files (was previously installed to Program Files (x86))

System is a
Lenovo Thinkpad T430
Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz
8GB Ram

Windows 8.1 Pro 64bit
Any ideas / help?

 

Did you also create a new "Player" or did you copy an old one from UserData -folder ?

 

No 32-bit plugins in the 64-bit folder?

 

Sorry for only replying now - just in case anyone has a similar problem. I set the Shortcut to "Run as Administrator", and the problem went away - have NO idea why, but hopefully that helps someone else.