Hello,

In our SMS for SMTP 5.0.1 Patch 187 server (Windows 2003) the Excel files (XLSX) attached are recognized as executable files. (and blocked)

A message with a XLSX attachment is detected and blocked because a rule, and in the Message tracking detail says:

Attachments: xl/printersettings/printersettings2.bin

I found this Excel 2007 new file format is (like) a container and includes several files organized and one of the files has BIN extension. I found this is why is detected (and blocked in our case) as executable.

My questions:

a) I wonder if it is correct to process this kind of files with the same restrictions as "regular" executable files or if it is not. (We block ANY executable files attached, no exceptions)

b) Is this kind of files (XLSX) as potentially dangerous as a regular executable file? (Possible to carry malware)

c) Is it possible to make an exception and how?

d) Is it possible to exclude the detection of BIN files inside XLSX attachments?

I will appreciate any useful information on this.

Thanks,
Raúl Batista
Droguería del Sud S.A.