Im using win 10 and cant seem to get it to install. I used it for years and for some reason it got uninstalled. Im sure it was me but i cant get it to install back.
https://ibb.co/PZSWkbm is the screenshot.

It seems to be saying that it doesn't know about the location that you've chosen.
It may be a permissions problem, or you may need to include that drive in the list that Windows knows about.

Not sure as I haven't used Windows in over 20 years but I suspect you will need to find and delete one or more folders that have been left behind when old instance was uninstalled. You may also have to remove a registry entry that points to the wrong place.

Neither of those. The problem is that Windows thinks that BOINC is still installed, and is trying to find the old installation package - but somebody or something has 'cleaned' that up, so it can't be found.

The easiest solution is to re-install the exact same version as you used last time. If that is still in your downloads folder, just double-click on it. That should lead you through a 'repair' process, following which the upgrade should proceed normally.

If you can't remember which version you installed last time, look at your account details at any project you've been attached to. Then, download the matching installer file from the archive folder, and try the repair from that.

There's a thread somewhere here with umpteen alternative clear-ups, but they're all more complicated. Try the easy way first.

Ah, thanks Richard.
Even with glasses I couldn't quite read the word "msi". :(

Beautiful! It took a few versions but it came up with the repair option. thanks everyone for the help. I really appreciate it