Its been a long time since i tried this, So i cant identify what I did to cause it .

Trying to drag multiple .sut ( brush files ) into Art-App it belongs. From the File Explorer window. Was able to do this many times in the past.

I noticed something ; when I use the search engine called
" Everything " from its window interface, if I call up the files in that window, then I'm able to drag and drop the files from that window, directly into the Art app. But cant do it from the File explorer window like I was able to do before.

Windows 10 home basic.
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One suggestion, I read in the windows 7 forum, there might be some registry change that happened. But I dont know about such things, just wanted to suggest a idea. Anyone can help ?