Can't drag and drop files, permissions issue?

Ever since i've updated to Windows 10 i've been having an issue with permissions which im unable to fix.

Basically all of my software and files located on a non-system hard drive appear to be restricted in one way or another despite the fact that i've manually set all of the permissions and made myself an owner of an entire hard drive.

Here are the examples of issues i've experienced:

1) I can't run any software i've installed on that hard drive unless im running it as administrator. This includes GOM player, Adobe Photoshop, Filezilla, Steam and other applications. I can run any software on a system disk without confirming it first as administrator though.

2) I can't drag and drop files from that hard drive to or from installed applications like GOM and VLC player's or Adobe Photoshop - it just won't let me since the cursor changes into a cross. If i installed the software on a system drive - i can drag and drop files (movies, photos, etc) just fine when i need to play something in VLC or edit files in Photoshop.

3) I couldn't use archives and drag and drop files from and to archives without a warning about "harmful files" popping up constantly until i installed winrar on a system disk.

4) Some files gotten locked if they were downloaded from the internet. I think i was able to fix that by editing permissions and security settings in gpedit.msc and explorer though.

Is there a reason why this keeps happening?

well, new here --- so question may be in inappropriate place. BUT, how do I go about defragging my system files which the analysis shows 14% fragged. it did the "C" files but won't do system although it is listed in the window.