Hi
 I have about 200+ VST plugin Instruments and about the same with FX VSTs. My computer is a 64/32 bit OS win7. My problem is it takes sometimes up to 2 hours to scan all the VST folders on the PC. When I do a install the plugin will install both the 64 and 32 bit versions. 64bit has 3 different vst folders/ 32 bit has the same, then there's vst folders under Common Files, Program Data not to mention the VST3 folders locations. It's got crazy!
Question : Is there a way to scan just certain folders? After I install a new VST instrument I know where it was installed. Is there a way I can direct the scan to a certain folder(s) and bypass the rest? Is there hope!  

If you go to Edit->Preferences, in "File->VST Settings" on the left, you will get "VST Scan Paths" at the top where you can add/remove paths. For 64-bit SONAR, I have removed the 32-bit scan paths (C:\Program Files (x86)\Cakewalk\Vstplugins) although I do have the 32-bit plugins installed.
 
Also on that page, I have Scan Options set to "Manual Scan" and checked "Rescan Failed Plugins." I only run the scan after I know I have installed/removed a VST, rather than leave it automatic or on startup.
 
2 hours is incredibly excessive. Which version of SONAR are you running?
 
FWIW, I only have the following two paths in my 64-bit VST Settings:
C:\Program Files\Cakewalk\Vstplugins
C:\Program Files\Common Files\VST3
but am also religious about installing to only those two directories.

Is it possible you have an error window open behind the Sonar main screen that is preventing the scanner from finishing?

Look in the taskbar to check for what Mudgel references. I have a couple thousand plug-ins, and to scan all of them takes a minute or two.

Also, which update are you on? There was a bug a couple of updates back that could cause this, but has since been fixed.

SONAR recursively scans all the folders in the scan path every time. It might be helpful if you publish your scan path from Preferences > File > VST Settings
 
As mentioned above consider eliminating 32 paths while running 64bit SONAR. If there are a few 32bit plug-ins needed for 64bit SONAR move them to a separate path so it is possible to remove the bulk of the redundant plug-ins.
 
Still 200+ plug-ins is not that many and should not take minutes to scan.

Yup - I have around 900, and it takes next to no time at all when I launch Sonar.
 
I too only have 64-bit 3rd-party plugins available in any of the paths in the VST search paths in Preferences, and only point to the 64-bit Cakewalk plugins and the VST3 path.  I direct all installs to use the 64-bit Cakewalk plugins folder, and do not install any 32-bit plugins anymore whenever possible (some installs just put them out there with no way to discourage them from doing so, but no 32-bit plugin paths are referenced by my 64-bit Sonars).
 
Bob Bone
 

As mudgel commented, the only time my VST plugin scan stalls is when there is a problem scanning one of the plugins, in which case a pop-up window will open (but will be hidden behind the other windows).  If I minimize the main Sonar window, I can then see the pop-up window, and either click on OK or close it.   Then the scan continues.
I also have many plugins, but after the first initial scan, any future scans go very quickly.

Thanks for all the input I'm going to try scanning Failed Plugins and see if that works

Very informative thread, I was having a similar issue with lengthy scanning, like SpaceE. But it wasn't 2-hours! Anyways, I'm gonna manually change the path of the scan, too. Thanks for the info...