Something is indeed wrong! I tried everything from Repairing Studio installation to deleting all Plugins as per SDL reset protocol! Nothing works at all. This is very frustrating. 

I even reinstalled from scratch, but still that error!!! 

8712.logs.zip

here are the logs just in case they can be of use to you in resolving this issue.

https://gateway.rws.com/csm?id=kb_article_view&sysparm_article=KB0039395

I did everything also as per the above!! Nothing works.

 even the FreshStart application does not work, and I made sure to run it as an Admin.

Sameh Elsharkawy Support Case Id : 00567241. Support case has been logged for your assistance. Please check your SDL Community email address for updates.

I had to use Iobit uninstaller to fully uninstall SDL Studio, and that required deactivating the license and reactivating it from my account. SDL studio worked well. I created a backup of the plugins folders and pasted them in place in the Studio path and to my surprise, it worked after having to remove just one plugin (Report viewer)!!! So my question is why didn't it work with the previous installation when I had all plugin removed!! Why did it only work after fully uninstalling SDL studio with an advanced uninstaller? 

It seems that I will have to create an image or a restore point before attempting to use the Notifications plugin again, because of situations like these Paul where you just lose one full day doing nothing but trying to figure out what went wrong. Thanks  for creating the support Case on my behalf. I hope the log files I sent are useful for SDL support to be able to resolve the mystery. 

Happy New Year in advance.

Sameh