Unfortunately, your assessment is not true - there have been and will again be (and probably are right now) ways to trick OE into executing attachments even without the user opening them.

I also know for a fact that there is indeed a list somewhere and a way to modify these permissions, but unfortunately I only vaguely remember reading about it. As I'm on Linux, I don't even have a way to look for that.

In the long term, the best advice anyone can give you, although I realize this does nothing to solve the problem at hand, is to move away from the trojans called IE and OE and use other software such as Mozilla to browse, maybe its builtin client for mails, or maybe PegasusMail, or the excellent TheBat! (but it's cashware). The latter tend to be much, much lighter on your system as well.

Maybe there are constraints which bind you to MS software, but if at all possible I'd give the options a long hard look and try to make them work.

Ok, now maybe someone else can come along and actually help you. :^)

Makeshifts last the longest.