So I wanted to install Borland C++ 3.1 under DOSBox to compile something ancient.  I’m on a MAC so MS-DOS player is not currently an option.  I have disk images, which p7zip can happily break down into files, giving me a bunch of files in a single directory, the perfect thing to mount as a ‘disk’ under DOSBox.  However I had subdirectories with patches, source and other stuff in my virtual ‘floppy disk’.  And the installer bombed.  Turns out it wasn’t any file limitation, or anything in the guest C: drive, no the Borland installer doesn’t like sub directories on the install source.

Remove those, and it’ll install just fine.

Also, maybe it’s the weird Borland extender, but Borland C 2.0 runs WAY faster under DOSBox than version 3.1