Just out of curiosity (since this is not a blocking point for us), but maybe someone has experienced this before:

We are using Mail::SendEasy to send mail from our application (Windows environment), which worked fine so far. By chance I found out that, if I use the module from the Windows command line, i.e. perl -we "use strict; use Mail::SendEasy;...", sending mail always fails and we get the error message

MAIL FROM error (500 .....: unknown command.)
[download]

If I put exactly the same Perl expression into a file and execute with perl -w myfile.pl, it works.

I now just would like to ask if someone, by chance, already has had a similar experience on Windows, or has some idea where this difference in behaviour comes from. Please - I do NOT want you to spend much time for thinking about this question! As I said, it is not so urgent (we don't intent to send mail "from the command line"), and if it needs to be done, I can always put together some "minimal example program" and put some additional logging into Mail::SendEasy to trace what is going on.