Terrified by Batch Files

Recently several emails have not reached their destinations, though they were sent to valid addresses, and I received no error messages.

All the messages had a particular attachment, consisting of a file created by zipping a folder containing instructions for connecting to a web site that I manage. There were three files in the folder. A batch file that opened a DOS window to make an ftp connection to the site, a text file that contained information required by the batch file, and another text file giving instructions. I needed to send all that to other officers of the association that owns the web site so they can operate it in the event of my sudden demise.

Other emails, including ones in which I assured intended recipients that I’d sent the information, were delivered promptly, but the messages with that attachment disappeared without trace; they weren’t even in the recipients' spam traps.

The destination addresses unable to receive the emails in question were on either Google, or ntl. When I sent a copy of the problem message to my icuknet mail box it arrived safely.

Eventually I renamed the batch file by changing its extension to ‘txt’ and changed the instructions to include a specification that the name should be changed back again before use, and the message was safely delivered with its attachment.

Google and ntl seem so terrified of batch files that they are even peering inside zipped folders in case one should be lurking there, and they hide the evidence afterwards.