I think I may have figured out what's happening. The batch file I am dropping on the DOSBox shortcut is located in the folder that is being mounted automatically by DOSBox. I think DOSBox looks at the folder the batch file is in as the "default" C drive and mounts it. Would that be correct?

When you launch DOSBox it will show the configuration loaded in the "DOSBox Status Window"

Don't drag batch files onto the DOSBox shortcut, that usage is only intended for very simple games.

DosFreak wrote on 2022-09-19, 22:28:

When you launch DOSBox it will show the configuration loaded in the "DOSBox Status Window"

Don't drag batch files onto the DOSBox shortcut, that usage is only intended for very simple games.

Well, I have been doing this for some time. My batch files are very short:

1@echo off
2cd wlfsrc\WOLFSRC\
3bc
4@echo on

This has not been an issue before. I just didn't know why it was mounting a C drive when I didn't use a MOUNT command. Is there a specific reason for not using drag and drop to use a batch file? Is there another way that would achieve the same result? The above opens Borland with the Wolf3D project open and ready for me to work on it.

You can do whatever you want, that's the pain and beauty of the PC but if you do something against the intent then don't be surprised when you see odd results.
Configuration files and dosbox switches are expected to be used. For the people that's too difficult for then launchers are used.

For figuring out the issue:
Check the dosbox status window, check the contents of your batch file for multiple mounts, if you are using "call" in the batch file then check if there is another mount in that batch file that call is executing.

I know what the status window shows. I also know that using the config file is recommended. I also know that dropping a batch file onto the DOSBox shortcut doesn't break anything. And if you look above you will see that my batch files don't include any of the things you mentioned. In fact, I've been thinking about putting the path statement into the batch files so that I can specify different executable paths for different applications. I put it in the config file simply because all of the projects I'm working on at the moment involve the use of the Borland 3.1 compiler, so that's the path needed to execute the compiler from the prompt in DOSBox. And, if you noticed, I include the instruction bc in the batch file so it launches the compiler automatically.

The only thing I wasn't expecting was the mount command to be executed automatically just from the batch file being dropped on the DOSBox shortcut. It has been about a year since the last time I used this (on my old Windows 10 laptop), so I had forgotten things. I am starting to remember more now. As for using different custom config files, when the only thing different is the information included in the autoexec portion of the file it makes more sense to me to just use batch files. Then you are only dealing with one config file, and the batch files need only contain the necessary information to set the executable path, cd to the appropriate directory and launch the application specified.

If you launch DOSBox by dragging a file onto it, it does indeed automatically mount the directory that holds that file. Otherwise it wouldn't be able to execute it.

jmarsh wrote on 2022-09-19, 23:37:

If you launch DOSBox by dragging a file onto it, it does indeed automatically mount the directory that holds that file. Otherwise it wouldn't be able to execute it.

Now that makes sense, and I don't know why I didn't think of that myself. I guess it's just part of getting old. Thanks for giving me the answer I was looking for.

jmarsh wrote on 2022-09-19, 23:37:

If you launch DOSBox by dragging a file onto it, it does indeed automatically mount the directory that holds that file.

Well that's a TIL out of this thread for me! I do a lot of mount changing, so that's something I'll have to experiment with.