Some Blitzmail client users can open enclosures I sent from Apple Mail. Can I fix this?
It may help if you set your preferences to plain text instead of rich text. To change this, go to Mail -> Preferences… -> Composing and set Message Format: to Plain Text. It may also help if the Blitzmail client user upgrades to the latest version (especially on the Mac). Please bear in mind that the Blitzmail client sometimes has problems with enclosures, and if this happens repeatedly it may be best for the Blitzmail client user to switch to another browser (at least long enough to get missing enclosures). Webmail is an easy alternative client for occasional use like this.