Hi.
Perhaps if you post an actual screenshot of the message along with telling us when it happens would be helpful to solving this.
You can type snippingtool in the start menu then hit enter to get the program to make screenshots. Then use the paperclip above where you type in advanced mode reply to attach the .jpg.
In the meantime, you can use CCleaner to clean the machine of all unnecessary files. When that's done, use it also to clean the registry itself.