If you use the scalar args form of system

...
system( "command \\path\\with spaces\\file" );
...
[download]

you'll may have problems with the spaces.

If you use the list form of the system function.

...
system( '\path\to\command.exe', '\path\with spaces\file' );
...
[download]

Note the use of 's rather than "s, to avoid the need to escape the backslashes.

cmd.exe will be bypassed and the spaces in the filename won't cause a problem. However, you will need to specify the full path of the command as well.

You can also avoid the need for using short filenames by quoting the filepath.

...
system( q[command "\path\with spaces\file" ] );
...
[download]

Which allows the shell to resolve the location of the command for you and forces it to see the quoted path as a single argument.

Note though, if your in an open environment, the risk entailed in allowing your shell to do this for you.