In DOS you typically cannot start applications from a different directory than their own, because they look for their data files in the directory you start them from, not where the executable is.

So you need two commands:

CD \MSFS5.S1
FS5.COM X

Doesn't help... 🙁

Are you booting from c: (or floppy) ?
Try:

1C:
2CD \MSFS5.S1
3FS5.COM X

For testing make a separate bat file e.g. MSFS5.BAT and copy the above code into it. Then try to run it after boot. This way you can find out if the problem is with starting the program from autoexec.bat specifically or the commands do not work even from a simple bat file. Then it will be more easy to find out what the problem exactly is.

Also note that this forum is for DOS games on *modern* systems. For old hardware and OS related questions ask in Marvin. Marvin, the Paranoid Android

Problem is, I can run this bat, but not from autoexec.bat itself.
Here is my autoexec.bat:

1@REM ===== PPLT INITIALIZATION ==========
2;@SET PROPATS=C:\GUSINSTA\PPL160
3@REM ===== PPLT INITIALIZATION ENDS =====
4C:\QEMM\LOADHI /R:2 /LO C:\DOS\SMARTDRV.EXE /X
5@ECHO OFF
6PROMPT $p$g
7PATH C:\QEMM;C:\DOS
8rem mscdex.exe /d:banana /L:D
9C:\QEMM\LOADHI /R:1 C:\MOUSE.COM
10SET TEMP=C:\DOS
11SET BLASTER=A220 I5 D1 H5
12REM set ultradir=c:\ultrasnd
13REM SET ULTRASND=240,7,7,7,7
14REM C:\ULTRASND\ULTRINIT
15C:\MSFS5.1\fs5.bat

After boot I see prompt. When I now type fs.bat game starts normally. But I want run it without typing anything. It should be started automatically after system was loaded.

You can't launch a .bat from a .bat without using the call command.

You can, it just won't return to the original .bat. Here it is not a problem, since it's the last command anyways.

So long as you explicitly 'exit' at the end of a bat file, control will return to the parent batch file.

Still no luck. I'm very curious: if Norton Commander can be started in this way, why not MSFS5.1?
call command didn't help too...
And one important thing: because I'm trying it under PCEM, if you using DOSBOX, please don't addcommands above into dosbox.conf file but into autoexec.bat itself.

OSH wrote:

Problem is, I can run this bat, but not from autoexec.bat itself.

After boot I see prompt. When I now type fs.bat game starts normally. But I want run it without typing anything. It should be started automatically after system was loaded.

Put a pause command above and below the C:\MSFS5.1\fs5.bat line. This way, you'll be prepared to watch the command run. It's possible the line is launching the program but the program itself is returning an error message; perhaps the pause after that will keep it in the screen or at least you'll be looking for it more directly.

I disabled ECHO command, so I see all messages during boot sequence.
I inserted PAUSE commands - nothing helps...

No one said pause can fix the problem. Pause/echo can help to determine what/where the problem can be. But you should say more than 'nothing helps'. Disabling echo is not necessary what's more you should enable it. And before/after commands you should insert echo commands to see if a command executed at all or something quits unexpectedly.
So you should put in your fs5.bat file ( or what is called from autoexec.bat):

1@echo on
2echo hey, I'm the other bat
3C:
4CD \MSFS5.S1
5echo MSFS starts
6FS5.COM X
7echo MSFS ends

And report back if you see all the messages and after execution ends the actual dir at the prompt is C:\MSFS5.S1

No. It seems, batch for MSFS wasn't executed. I don't see any messages from ECHO, and actual dir after execution autoexec.bat is still C:\
My MSFS directory is called "MSFS"

Here my autoexec.bat

1@REM ===== PPLT INITIALIZATION ==========
2@SET PROPATS=C:\GUSINSTA\PPL160
3@REM ===== PPLT INITIALIZATION ENDS =====
4REM DEVICE=C:\EMM386.exe AUTO RAM
5C:\QEMM\LOADHI /R:2 /LO C:\DOS\SMARTDRV.EXE /X
6@ECHO OFF
7PROMPT $p$g
8PATH C:\QEMM;C:\DOS
9rem mscdex.exe /d:banana /L:D
10C:\QEMM\LOADHI /R:1 C:\MOUSE.COM
11SET TEMP=C:\DOS
12SET BLASTER=A220 I5 D1 H5
13set ultradir=c:\ultrasnd
14SET ULTRASND=240,7,7,7,7
15C:\ULTRASND\ULTRINIT
16call C:\MSFS\fs.bat

And fs.bat

1@echo on
2hey, I'm other bat
3C:
4CD \MSFS
5echo MSFS starts
6fs5.com x
7echo MSFS ends

And config.sys:

1device=c:\qemm\dosdata.sys
2DEVICE=C:\DOS\SETVER.EXE
3REM DEVICE=c:\EMM386.exe AUTO RAM
4DEVICE=C:\QEMM\QEMM386.SYS RAM R:1
5device=c:\qemm\dos-up.sys @c:\qemm\dos-up.dat
6DEVICE=C:\QEMM\LOADHI.SYS /R:1 /SIZE=11520 C:\QEMM\QDPMI.SYS SWAPFILE=DPMI.SWP SWAPSIZE=1024
7DEVICE=C:\OAKCDROM.SYS /D:BANANA
8DEVICE=C:\MOUSE.SYS
9DOS=HIGH,UMB
10FILES=30
11SHELL=C:\QEMM\LOADHI.COM /R:2 C:\COMMAND.COM C:\ /P

You have missed the echo command before the 'hey...' message in your fs.bat, but you should have seen an error instead of nothing. So further testing is required. Put the call to fs.bat to the beginning of autoexec.bat and also put and echo before it. So the first 3 lines of your autoexec.bat should be:

1@echo on
2echo hey, I'm autoexec bat
3call C:\MSFS\fs.bat

Also put a REM before @ECHO OFF in autoexec.bat temporarily (REM @ECHO OFF).
This way you can check if 1. autoexec.bat is called correctly 2. whether a command within autoexec breaks the execution before the call at the end.

OSH wrote:

And one important thing: because I'm trying it under PCEM

Can you adjust the CPU speed in PCem? If so, slow it waaaay down so you have time to read messages that might flash off the screen.

Falcosoft, you won't believe, what was a cause...

https://imgur.com/a/Xn7C1

This is my config.sys. The cause was this small arrow behind ULTRINIT. I can't even reproduce this sign, so I give screenshot with config.sys. When I deleted it, MSFS finally starts normally.
BIG THANKS!

krcroft wrote:

So long as you explicitly 'exit' at the end of a bat file, control will return to the parent batch file.

Nope. It will terminate the command shell (or DOSBox). Try the following. (Note that "tmp1.bat:" and "tmp2.bat:" are the names of files to put the following commands in, not labels.)

tmp1.bat:
echo tmp1 start
tmp2
echo tmp1 end

tmp2.bat:
echo in tmp2
exit

Take out the exit, and the batch execution will stop at the end of tmp2. To get nested batch files, use call:

tmp1.bat:
echo tmp1 start
call tmp2
echo tmp1 end

tmp2.bat:
echo in tmp2

Sincerely,

Gene Wirchenko

Moved.