Hi Luke.

>I've updated some controls (treeview etc., from dbi-tech.com) in my app, and now I have to distribute the new version to my customers. Rather than forcing thousands of (soon to be irate customers) to uninstall and re-install the whole thing, I'd like to programmatically:
>
>- find out if they have sufficient admin rights; and then...
>- identify the old controls;
>- de-register and remove the old controls;
>- determine if the new ones are already installed, and if not...;
>- install the new ones.

Use an installer for this -- it can take care of all of these tasks and require the user to elevate to admin so there are no permissions issues.

>The corollary to the above is if the controls are build into the exe, do I have to include the ocx files anyway, and copy them to the \windows\system32 folder to register them, or can I do it by reference to the exe?

OCXs aren't built into the EXE so they need to be copied somewhere and registered. Note that they don't have to go into System32; they can also be installed in the app folder.

Doug