HelpDesk can fetch emails from any and multiple email accounts and convert them into tickets. Depend on your settings it allows:
When you use PHP Imap, please use a dedicated email address for it. Do not use the same support email address anywhere else in the system!
The php imap client will try to pull in the attachments from the email, but sometimes it is not possible due the way the attachments has been attached/sent. There is also a limitation on what attachments are pulled in (see your settings for which files you allow for the client) and how many attachments are allowed per ticket.
For example you have set 3 files per ticket and the ticket has already 3 files attached the customer does send more by email the attachments won't be fetched, only the text.
The most reliable and guaranteed way to attach files is via the client dashboard on each ticket.
The operator has access to the file and image manager and can link them straigth away in the support ticket. Make sure you use full site url's, otherwise your client cannot view them in the email.
For example if you attach an image make sure the image path is: https://www.yourdomain.com/files/myimage.jpg.