Microsoft Flight Simulater X Gold Edition Activation Error

Oh yes! That's the well-know FSX Acceleration pack validation error:

The registration of the FSX firstly installed does not pose troubles, generally as the one of the Acceleration Pack does. Once installed and launching back FSX you may get a 1-80004005 error, which will limit the use of your FSX at 30 minute of time. The solution, which is widely given on the Internet, resides into a faulty entry of the Windows Registry. To fix that, run 'regedit' from Cortana and launch that utility. It will show you the registry content. CAUTION, THAT CONTAINS SENSITIVE DATA! DO NOT CHANGE ANYTHING EXCEPT WHAT FOLLOWS! Expand HKEY_LOCAL_MACHINE\SYSTEM\CURRENTCONTROLSET\CONTROL\CLASS\{4D36E967-E325-11CE-BFC1-08002BE10318}. In the left column, double-click the UpperFilters entry (note! there may be there several {4D36E967-E325-11CE-BFC1-08002BE10318} entries; just find the one which holds UpperFilters). Thence three possibilities: either you will just read 'partmgr,' and just change that into 'PartMgr' -- with capitals -- and exit the registry by clicking to the upper right as registry automatically saves. Either you will find a '0' value; change it too to 'PartMgr' and idem. Or, at last, you may find other values of which 'partmgr'; some advice to first backup tall those, then erase everything except 'partmgr' (you will turn to 'PartMgr'; exit idem, and once the registration performed, you may paste the backup back). In all cases, once the Registry entry fixed, restart your PC and then launch FSX. The registration panel will pop up!