If Error 1-80004005 is encountered during FSX Acceleration activation, follow the steps below to remove it:
1) Locate the entry below by regedit.exe
HKEY_LOCAL_MACHINE\SYSTEM\CURRENTCONTROLSET\CONTROL\CLASS
\{4D36E967-E325-11CE-BFC1-08002BE10318}
2) Look at UpperFilters key. It should contain “PartMgr” only.
3) If the key shows something more, mark down what they are
before editing the key to read “PartMgr” only.
4) Start FSX, the activation dialog should be prompted.
5) Proceed and let FSX start, then exit FSX.
6) Edit back the registry key with the previous content. (This step may not be required.)
FS Times 
Thanks (from the year 2020)
It got my old boxed copy of FSX + Acceleration working on Win 10 :)
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Great, glad that it helps after 10 years.
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Yeah…my son will be thrilled this seems to have worked with the acceleration problem on our computer…hopefully I have not messed with anything else on the system!
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Good Luck.
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tom i already do the changes and i have the activation key window… but now when i enter my key it says that there is an error trying to connect with the server and i put to do it by phone and says it cant find the id that is need for the phone activation…. what i can do???..
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Hi Lucas,
I have no idea what’s wrong in your case since I haven’t encountered it before. Perhaps try reinstalling the whole FSX again. Sorry couldn’t help much.
Tom
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How Tom Tsui arrived at this successful solution to the problem I will never know! If you’ve loaded Accelerator and can’t activate it because of an error code this IS the solution. Removing just ONE word from just ONE of thousands of registry keys does it! Little or no help offered by Microsoft on the matter.
Many thanks.
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You are welcome, Dan.
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It’s brilliant, I’ve been looking everywhere to fix this. No support from MS in this case.
Thanx!
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Hi Bert, Glad that it helps.
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I have been installing and un-installing the game for more than 4 hours, until I followed those steps are perfectly OK for editing the registry to make the game works.
Thanks, mate!
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You are welcome, Keith.
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This fix works great !!!! “BUT”, you MUST do everything exactly like the instructions say because you are messing with the “Registry” of your PC… Write down everyhting like they say, and be very observant of any “spaces” between words or KEY values…
Thanks, Ray
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Indeed. Tom
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