Intalling the 737 immersion I get the following error!!

Installation Error: System.UnauthorizedAccessException: Access to the path 'F:\Program Files (x86)\Steam\steamapps\common\FSX\SimObjects\Airplanes\PMDG 737-800NGX\panel\panel.cfg' is denied.
   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
   at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
   at System.IO.StreamWriter.CreateFile(String path, Boolean append, Boolean checkHost)
   at System.IO.StreamWriter..ctor(String path, Boolean append, Encoding encoding, Int32 bufferSize, Boolean checkHost)
   at System.IO.StreamWriter..ctor(String path)
   at a.ah.d()
   at VFXCentral.MainWindow.A(Object , DoWorkEventArgs )
   at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
   at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)

some help???

I have been having similar issues and PD3 V4.4 stops working due to this VFX Central... I also cannot seem to insert file to show problem in support