What are the allowed attachments?
We forward emails with attachments for up to 10Mb per email (including message and attached files) and up to 50Mb for our premium members. Of course, the end mail server need to be able to accept this attachment size. For example, Gmail limits it to 25Mb.
We refuse some attachments for security reasons. The list is basically the same as the other main email providers.
Here are the extensions that are not allowed on ImprovMX:
.ade .adp .bat. .chm. .cmd.
.com .cpl .dll. .exe. .hta.
.ins .isp .jar .jse .lib
.lnk .mde .msc .msc .msi
.msp .mst .nsh .pif .scr
.sct .shb .sys .vb .vbe
.vbs .vxd .wsc .wsf .wsh

Questions? We’re always here to help.
We pride ourselves on offering incredibly reactive support, free of charge. Premium users get priority, but we answer everyone.
Still unclear? Watch a step-by-step video
Andy, a happy user from ImprovMX, has recorded a step-by-step video to explain how to set up your business email alias.