Welcome to the forum.
The message is usually easily dealt with. I haven't checked
the article as you didn't include a link but I'm guessing it
involved deleting a couple of files and then using the HHP file to
open the project.
What is more worrying is that you cannot create a new
project.
Have you tried opening one of the supplied sample files?
Are your projects stored locally and not on a network?
Have IT given you a new profile to log on with?
Has anything else changed in your environment?
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