4.5 still has this plugin scanner issue. I have NVidia Geforce GT 740 and Windows 7 Service Pack 1. Separate pluginscanner.exe which started all problems in Windows 7 doesn't work even with all gpu drivers uninstalled (tried in safe mode too to be sure - used https://www.wagnardsoft.com/ ). Still what a music program with simple gui vst detection has to do with gfx drivers is beyond me (I make 3D graphics too). As a workaround I tried to copy "c:\Users\User\AppData\Roaming\PreSonus\Studio One 3\x64\Plugins-en.settings" and "c:\Users\User\AppData\Roaming\PreSonus\Studio One 3\x64\Vstplugins.settings" into Studio One 4 directory equivalents but it doesn't work. Here is excerpt from "c:\Users\User\AppData\Roaming\PreSonus\Studio One 4\x64\PlugInScanner.log" . What is "Async scan call timed out. Server process crashed"?
2019/07/13 16:36:42.016 [Info]: UI Status: Scanning 1 of 120: 3rd_Bass
2019/07/13 16:36:42.017 [Info]: Scan next file in scan process: 3rd_Bass
2019/07/13 16:36:49.639 [Error]: Async scan call timed out. Server process crashed
2019/07/13 16:36:49.639 [Info]: UI Status: Failed to scan 3rd_Bass
2019/07/13 16:36:49.640 [Warning]: Crash while scanning 3rd_Bass in a new process!
2019/07/13 16:36:49.640 [Info]: UI Status: Waiting for plug-in scan process...
2019/07/13 16:36:49.730 [Info]: UI Status: Scanning 2 of 120: 7amp-flyingecho-1
2019/07/13 16:36:49.740 [Info]: Scan next file in scan process: 7amp-flyingecho-1
2019/07/13 16:36:57.313 [Error]: Async scan call timed out. Server process crashed
2019/07/13 16:36:57.313 [Info]: UI Status: Failed to scan 7amp-flyingecho-1
... and it goes on and on with all other plugins