I suggest the following which worked for me.
Open the Photoshop program folder and open the Plugins folder. Move all the plugins to a separate empty folder on your desktop. Be sure there are no files in the Plugins folder
Next restart Photoshop 2015. If it opens correctly replace the plugins, one by one, into the Photoshop Plugins folder and restart Photoshop 2015 after each individual replacement. When Photoshop 2015 stops starting correctly you have found the offending plugin(s).
After doing the above I found two plugins that caused my problem. Downloading updates for the offending programs that were created to solve Photoshop 2015 plugin problems and installing them solved the issues for me so I can use those plugins again.
Also I found this program Photoshop Fix Toolbox
https://www.fixtoolbox.com/photoshopfix.html