Thread: Inserting images in PM?

Unfortunately the software we use, vbulletin, does not have this function.

I've considered implementing it in the past, but ultimately I figured it's not worth it as it's a bunch of work to do it in the first place, then there is the long term maintenance and even more work in upgrades and migration.

As others pointed out the best option is to use either email or external hosting and post links to it.
In fact some people do that in forum posts, too, which is not ideal because over the years those external images disappear and the old threads become less meaningful. In a PM it's not too important because those are private communications and largely temporary without long term value like the public discussions.