Hi have recently started getting the dreaded error box coming up saying very sorry but fatal error has ocurred and FS has to close it references sim1.dllAnyone have any clues as to cause?Many thanksClive

Someone else had this problem about a week ago and said the problem was a bad scenery.cfg file. Hopefully he will see this and jump in and tell what he did to fix it. keith

I found a lot of discussion concerning this error using the search term "sim1.dll". There are a lot of reasons for this error to occur, to include using the nocd, a corrupted scenery.cfg (areas and layers to not match or out of sequence), or a bad install of video drivers. Hope this helps.Jim

Many thanks for tips For interest I thought I had solved it asI realised I had recently upgraded the direct x to 9c without updating the video drivers for the ge force vdeo card. All went well for 10 minutes at kjfk when it happened again. Have now changed the sim1.dll file for the original.Have saved the old one as I noticed the date on it was more recent. Have also checked scenert cfg file with no apparent errorsbest regardsClive

Clive,I also did a Google search for sim1.dll and found that it's one of the dll's in the Modules folder that provides code for various other operations in FS9. For instance, an author of a gauge may use it to control parts of his/her gauge or an air file. So, if you recently installed a new aircraft with it's new gauges or air file, there might be poorly written code to properly use the sim1.dll. I also found that the code in sim1.dll is quite complicated and is constantly working which could cause a conflict. I'm no expert on writing code or complicated processes such as .dll's so I hope you understand what I've written and can apply it to your scenerio. Good luck.Jim

Hi and many thanks for replysThe saga continues !!I have spent some time now trying to resolve this issue.The items downloaded and installed prior to the first error message were:-1) the pai military packages2) b747 panel file name b747dlx5.zip from flight sim .com3) Directx upgraded to 9c4) nvidea drivers upgraded from nvidea for geforce graphics cardactions1)military packages disabled2)747 panel uninstalled, all gauges removed from gauge folder.3)as is 4)as isresults.Sim1,dll error still occurs regardlessIt may and has ocurred during the loading of elevation data during start up or the sim may load default at meigs when it will only be a matter of time before the message shows.I have tried with various percentages of AI traffic, but the only time the sim will run so far with no error message is when the ai percentage is set to zero. even 1 or 2 % will cause the message.Am I going round in circles and missing the obvious??can anyone think of any other possibility or corrective action please?I will be posting this on both the avsim and flight sim forums for your infoMany thanks Clive

I dont know much about this but would a System Restore work?

I did wonder but when I checked the system restore it would only allow back to the start of february for some reason. January restore points were not available. As this has been ongoing since the latter half of january there would seem to be no point .I thought the previous months restore points should have been available and have no idea why they are notmany thanks for the suggestionClive

I hope you find a solution soon!<<< I thought the previous months restore points should have been available and have no idea why they are not >>>Sys Restore has a fixed amount of disk space. As it gets filled with Restore Points (RPs) and runs out of room it begins to get rid of the earliest RPs to make room for the latest ones.What you can do (**once everything is sorted outa 100% on your computer**) is create a RP and then run Disk CleanUp (ProgramsAcessoriesSystem ToolsDisk CleanUp)Select the "More Options" Tab & then run the System Restore cleanup! This gets rid of all but the most recent RP - thus using the alloted Sys Restore space in the best way; preventing it getting clogged with old RPs.http://forums.avsim.net/user_files/105907.jpg:)

Clive,Sorry to hear you are still having problems with the dreaded sim1.dll error. That 747 panel you installed also installed the fssound.dll in your modules folder. Make sure that has been removed too and the "OLD MODULES" entry that was required in your FS9 config has been removed (unless you're using fssound.dll for another panel). Unlikely this is the cause of your problem but might as well clean up a little just in case. There's a version 6 of this 747 panel at flightsim date Jan 16th. I would go through each one of the gauges/cabs this panel installed and make sure it did not overwrite one already installed. If it overwrote a gauge for an existing aircraft, this could be your problem. As I stated in an earlier post, the sim1.dll is very busy and constantly answering calls/instructions from various gauges and .air files (that's my understanding anyway from my research on the Internet). A poorly written air file or missing gauge/cab could therefore be causing the error message. Hope you can get this resolved soon.Jim

Ok I'll check that, from your research is there any chance scenery files could affect the dll?

"Ok I'll check that, from your research is there any chance scenery files could affect the dll?"No indications scenery (.bgl) files are affected by this module. Just gauges and air files. I'm still looking though.Jim

Here's another possible solution: http://dcforum.simforums.com/cgi-bin/dcfor...orum=DCForumID1. See Thread 14. A person using FlightSim Manager found out that while the utility was checking aircraft for errors, it loaded a dummy .air file (with 0 bytes). Of course, at startup, the system was trying to read this .air file (to load AI aircraft) and the system subsequently crashed with the Sim1.dll error message. Perhaps this is what is happening to your system.Jim

Hang out the flags, kick the tyres and light those engines!!!WE,RE FLYING !!!Ok back on the ground First off I had narrowed it down to a suspect a/c in the Delta Fleet as majority of time the crashes ocurred in the USA.However the crashes still ocurred at a much lesser rate in other parts of the world.Anyhow as per your suggestion I did a search for all .air filesand found not one but severaland the first was a Delta connect crj200 comair 25th anniversary from PAIthe second was a KLM Boeing 777-300 from Meljetthe third was a BAE concorde not sure of sourceAlso found a PAI A333 with a .air.air extensionAnyway have quarantined those filesReturned the delta fleet to flying duties except for crj200, KLM777 and concorde which remain firmly in the hanger.As I speak am located at he end of RW32L at O'hare with all sliders set at max in real weather (snowing and overcast) whilst every a/c on the planet seems to be attempting to land before the airport closes !!!No dreaded error message .........yetMany, many thanksPs There was no file produced by FSmanager as far as I can tell Best RegardsClive