Aircraft Error in MB

[Ravenna]

Good Morning,
I am having trouble using Stuart Green's WW1 fighters in Mission Builder. Every time I select his Fokker VII, Roland or Pfalz D.III I get an error message when I press "fly now". I have checked the sound folders and the panel folders and they seem OK. All the aircraft show up in Free Flight. When I replace the SG aircraft with an Aerocrate aircraft (in the same mission) the mission works.
To compound the problem the same thing has started to happen with Baldy's Airco DH.9, which I have placed in missions without any problem until yesterday. (Mike, I promise I haven't broken your DH.9)
Interested in your thoughts on this annoying glitch.
Cheers,
Ravenna

[The B24 Guy]

Hi Ravenna,

Just a thought. Check the DP file something in the back of my brain says something with AC speed?

Regards,
B24Guy

[Captain Kurt]

Somewhere in the back of my mind is maybe check the dp for the entered service date. If the mission date is earlier than the entered service date it may not load the plane in the mission.

[Ravenna]

Thanks guys. I'll check out the DP.
Cheers,
Ravenna