"Missing Plug-ins" message when opening old projects...need help/suggestions :)

Going through some of my old projects, I'm encountering the pop-up warning me that there are missing plugins and that they will be held with placeholders until on a system which has the plugins in stalled.
Thing is, the plugins are there, i've scanned and it's found them, I am using the 32bit version of x1 although i've tried on 8.5 and x2 also (all 32bit versions as plugins were all 32bit in the old projects)
So is there any way to sort this? Foolishly I didn't write down or save the presets for the synths in a different location, as I was under the impression that sonar would save all that information with the project. Although I do save the presets and such these days.

So, any idea how I can get these projects opening with the original synths?