I receive the following error when I turn startserver.bat:

Error: Could not find or load main class @libraries.net.minecraftforge.forge.1.18.1-39.0.10.win_args.txt

I've updated to the latest version of Java and Forge on the machine. Any ideas?

Not sure if this will help you like it did me but i was getting the same error when trying to run the server on Java 18 i had to install Java 17 now its working fine for me

Thanks. That's what I had to do and then it worked.