The SpamExperts email filtering service allows you to set maximum attachment sizes, as well as reject emails with certain types of attachments (for example, executable files).
To control these settings, login to your control panel and select Virus and Spam Filtering from the top menu.
From the SpamExperts dashboard, look for the Email restrictions area.
To manage what types of attachment can be sent, select Blocked extensions. There will already be a list of common extension types that are usually dangerous. Please note that any whitelisted senders will still be able to send attachments with these extension types.
To manage the maximum attachment size, select Email size restriction. Please note that any whitelisted senders will be able to send attachments larger than this limit. You can either reject or quarantine messages that breach this limit.