hello everybody,Flying from KMSP (BluePrint simulations) to KDEN (Imagine Simulation) I got fs 9.1 shutting down on me.Error message stating that atc.dll caused the error but when opening the technical info I see quite a number of probable causes.Now I have read somewhere about act.dll but I can't find the thread anymore.I am using Windows XP 64bit.In the past I have flown quite a lot on Denver (from Imagine Simulation) and I have never experienced this kind of error.Can anyboy point me in the right direction?ThanksLuc BrusselmansBelgium

Luc,Are you using AI traffic?If so.Turn it off and do a test.Same problem?

Luc,Are you using AI traffic?If so.Turn it off and do a test.Same problem?

Vaughan,no, I don't use any AI traffic, except for the default AI included in Fs-9 (maybe I should....).I have read somewhere this crash can be caused by a problem with ATIS frequencies but I don't know where I read it or how to solve it.And I have never experienced this kind of crash with KDEN.Thanks anyway.Luc BrusselmansBelgium

Luc,I should have said:In MSFS, set (verify) your AI traffic to 0 (zero), then test again.

Vaughan,no, I don't use any AI traffic, except for the default AI included in Fs-9 (maybe I should....).I have read somewhere this crash can be caused by a problem with ATIS frequencies but I don't know where I read it or how to solve it.And I have never experienced this kind of crash with KDEN.Thanks anyway.Luc BrusselmansBelgium

Hi Luc,It's not related to Ai traffic but to a long-standing bug in FS9. It occurs on a change of frequency (TWR to GND for example) and is associated with other frequencies used in your plan. I've experienced it when a frequency at EGLL is the same as one at LIRF.Try entering removeatc=yes in the General section of FSUIPC.INI. That will stop some instances of the bug but not all. I've beaten it by using AFCAD to change one of the frequencies at either of the airports in your plan but that may introduce the problem at previously unaffected airports.It's a pain but fortunately is quite rare. If it occurs when you switch to a frequency at KDEN try editing the AFCAD for KDEN and change the frequency to another. GND usually has more than one anyway.

Hi Luc,It's not related to Ai traffic but to a long-standing bug in FS9. It occurs on a change of frequency (TWR to GND for example) and is associated with other frequencies used in your plan. I've experienced it when a frequency at EGLL is the same as one at LIRF.Try entering removeatc=yes in the General section of FSUIPC.INI. That will stop some instances of the bug but not all. I've beaten it by using AFCAD to change one of the frequencies at either of the airports in your plan but that may introduce the problem at previously unaffected airports.It's a pain but fortunately is quite rare. If it occurs when you switch to a frequency at KDEN try editing the AFCAD for KDEN and change the frequency to another. GND usually has more than one anyway.

Ray,That's the explanation I was looking for. I knew that I read it some where but couldn't remember where...I'll start with changing the fsuipc ini file. If the problem still pops up at Denver I'll try to change some of those frequencies.Thanks for the tipLuc BrusselmansBelgium

Ray,Could AI traffic at a nearby airport changing frequency / flight plan cause this problem?Or is it only the users aircraft/flight plan?

Ray,Could AI traffic at a nearby airport changing frequency / flight plan cause this problem?Or is it only the users aircraft/flight plan?

Ai traffic cannot cause this. If you notice this only happens immediately after a frequency change in your own flight and virtually always at the arrival end.

Ray,Thanks for confirming.I do not use AI or FS9's ATC.I have never had the problem with FS9.Yet!

Ray,Thanks for confirming.I do not use AI or FS9's ATC.I have never had the problem with FS9.Yet!

Many haven't and it's still pretty uncommon. I should also say the problem can occur with Radar Contact but it's not RC's fault but the underlying problem in FS9.

Many haven't and it's still pretty uncommon. I should also say the problem can occur with Radar Contact but it's not RC's fault but the underlying problem in FS9.

Ray,This confirms my suspicion because at the time of the crash I was using RadarContact. (As I always do)thanks for sharing this infoLuc BrusselmansBelgium

Luc,When I saw you don't use FS9's ATC and no Ai I thought you must be a VATSIM pilot but I'm pleased to hear you use RC. :(

That atc.dll error could occur when using any other atc application alternative. I had the same error flying KMSP - KDEN with RC and it was cured by the FSUIPC.ini entry as described by Ray."removeatc=yes" should be used when using RC, PFE, VATSIM, or other application of that type. It does not shut down FS AI movements, just basically FS ATC comms.

That atc.dll error could occur when using any other atc application alternative. I had the same error flying KMSP - KDEN with RC and it was cured by the FSUIPC.ini entry as described by Ray."removeatc=yes" should be used when using RC, PFE, VATSIM, or other application of that type. It does not shut down FS AI movements, just basically FS ATC comms.

Too All,Today I flew the same route with RC but now with the "removeatc=yes" in place.No crash....So, I am happy again.thanks for aal the help here.Luc BrusselmansBelgium

Too All,Today I flew the same route with RC but now with the "removeatc=yes" in place.No crash....So, I am happy again.thanks for aal the help here.Luc BrusselmansBelgium

That's good news Luc, you're welcome. :(