As a security measure to prevent potential viruses, a few SMTP servers (such as Gmail) don’t allow you to send executable files (such as files ending in .exe/.bat/.com) that could contain damaging executable code.
Now, these SMTP servers won’t accept these types of files even if they are sent in a zipped (.zip, .tar, .tgz, .taz, .z, .gz) format.
So, if you want to send a safe executable file (e.g. test.exe) in our emarketing software, please rename it to ‘test.ex_’ or other names and compress it first, and then tell your contacts in message content.
To know more detail about this, please refer to the following Gmail article: