The SYSTEM.TSH file is not used by Windows during the bootup process, only the SYSTEM.INI file.

According to the note at the top of your SYSTEM.INI file, some "System Configuration Utility" (whatever that is), made a backup copy of your original SYSTEM.INI file and named it SYSTEM.TSH. It then made numerous changes to your current SYSTEM.INI file. If you compare the two (TSH and INI), a lot of lines are missing and there are many changes to the lines that are left.

The SYSTEM.INI file doesn't really "run" like a program. It's a list of configuration settings like the Windows registry. Some of the lines can cause Windows to load various DLLs, others to launch EXE programs and others are simply configuration settings for things like installed fonts, cache sizes etc.

Apparently one of those DLLs or EXE programs listed in both your SYSTEM.INI and SYSTEM.TSH files are causing your system to shutdown on bootup. It could be because one (or more) of the DLL and/or EXE programs is corrupt or malicious or it/they could be causing a conflict with something else on your system.

The last step we took, trying your original SYSTEM.INI file, was with the hope that the problem was only with something in the new SYSTEM.INI file ... which didn't work.

The next step (in this process of elimination) would be to temporarily delete one section at a time (in the new SYSTEM.INI file), reboot and see if it still tries to shutdown. Once you've found the problem section, then start deleting just one line at a time from that section, reboot and see if it worked. Hopefully you'll eventually discover the line (or lines) that are causing the problem.

I say "hopefully" because it's sometimes a particular combination or even a sequence of events that can cause the problem. (Load A before B and it doesn't work, but load B before A and everything is fine).

Another thing you might try is booting up to the Startup menu and selecting the "boot with logfile" (or similar) option. As Windows is booting up now it will be adding what it's loading and doing to separate lines in a file named "C:\BOOTLOG.TXT". The last entry (or near to the last entry) should be the program causing the auto-shutdown problem. (Since Windows won't stay running for you, you'll probably need to boot from a Windows Startup/Boot diskette in order to view the C:\BOOTLOG.TXT file).

Gotta run for now, (off to work). Holler if you need some help with any of the above.