Reaper VST loading is really slow

I recently formatted and upgraded to Windows 10, reinstalled everything and Reaper seemed to work really stable and efficient. Since two days, Reaper's performance has decreased suddenly. Especially when I load heavy vst libraries, like omnisphere 2, it looks like 30 seconds to open, and browse into presets folder is painful. Why? The only change I made is upgrading OS and changing Interface (from zoom to RME). Here my configuration: Intel Core i5 3330 3.00 GHz Socket 1155 LGA 16 GB DDR3 dual channel ASRock Z77 Extreme 4 Samsung SSD 840

... maybe some AntiVirus software is scanning things?

Well, i have same issue since something like version 5.20. At first I thought its problem on my side, but it was getting irritating and so i checked in cubase and same plugins load instantly, but in reaper loading massive or kontakt for the first time can take even a minute.

Mik - you obviously have something somewhere set weird in Reaper. I and a bunch of others have no issues with slow loading plugins. Mind you I only have a half dozen libraries in Kontakt, so I suppose if you have a gazillion libraries that ould slow things down a bit but in that case I would expect to see the same issue with other DAWs. I assume you tried doing a portable install and comparing load times with your existing installation?

Ha Ha! Can't win some days, can you? But logically, since a clean portable install is done expressly to avoid changing anything in your existing install, unless you/your friend reinstated the existing plugin/template/etc paths and picked up the same problems as on the original install, there is no way a portable install can mess with the settings in your original.

I may well be down visiting friends in Shoreham later this year, so if you fancy a visit - maybe combined social and Reaper wrangling, maybe we could work something out?

All good, Mik - I am an Old Retired Waster with nothing but time on my hands... or so Mrs. Terrible* tells me. *cf Ivan The Terrible. Was once introduced to a customer as "our manager, Mr. Terrible, will help you, sir..."