VSTi Folder - where are the instruments?

Hi, 64-bit Reaper on 64-bit Vista - newbie. Excellent software. My only query is this: I have included the path of the VST instrument plugins in Options - Preferences - Plugins and yet when I try to insert a virtual instrument on a new track there is no reference to the VSTi files. I've rescanned, cleared the cache and rescanned and yet - nothing. I've got NI Pro-53 and B4, Korg Legacy and some of the East West stuff and yet none of it will show up when I try to add a new track. I've even created a folder called c:\vst and added it to the plugins path, cleared the cache and restarted Reaper to no avail. As a newbie - am I missing something obvious here? Thanks!

The thing I'm getting: by default all VSTs are first put in VST section of FX chain, not VSTi. So you have to go there (right under DXi) and find your instruments, click on them one by one, press F2, and check "Categorize as Instrument". Give it a meaningful name. I hope I'm right on the spot.

It may be that your VSTi's are not 64 bit compatible. Try installing the 32 bit version of Reaper and see if they "appear"? The 32 bit version works well under 64 bit OS's according to all I have read here on the forums. I;m still on 32 bit XP Pro myself... D

Mea culpa and thanks 

Thanks to everyone who has replied. I'm a guitarist (boo!) who works in IT (boo!?) so VSTi is something new to me - basically, if I can't stamp on a piece of equipment to make my guitar sound "wooshy" then I'm stuck - so all of your input has been excellent. I tried 32-bit Reaper and yes - my VSTi all appeared and made an appalling noise. Appalling, because I'm a guitarist who thinks that playing "Chopsticks" on a keyboard is the mark of a particularly dextrous genius, not because the software wasn't working properly... I upgraded my PC to 8Gb RAM, so it seems that Reaper will have to run in the 32-bit address space and I'll have a few gig left over for... er... printing? Anyways - thanks to everyone who responded and thanks for your help. Reaper is still ace, though - however many bits it uses.