Gmail blocks for security reasons email attachments with the following extensions:
.ade .adp .bat .chm .cmd .com .cpl .exe .hta .ins .isp .jse .lib .lnk .mde .msc .msp .mst .pif .scr .sct .shb .sys .vb .vbe .vbs .vxd .wsc .wsf .wsh
Gmail does allow archives such as .rar and .zip, but they can not contain files with the extensions listed above and they can not be password protected.
To send an attachment that can not be sent with Gmail, share the file from Google Drive as if you were trying to share a file that was too big to send.
.ade .adp .bat .chm .cmd .com .cpl .exe .hta .ins .isp .jse .lib .lnk .mde .msc .msp .mst .pif .scr .sct .shb .sys .vb .vbe .vbs .vxd .wsc .wsf .wsh
Gmail does allow archives such as .rar and .zip, but they can not contain files with the extensions listed above and they can not be password protected.
To send an attachment that can not be sent with Gmail, share the file from Google Drive as if you were trying to share a file that was too big to send.