Doesn't really give us much to go on from the error. I would start with what Phenomenal said check your DLLs.
.Net Framework 4.6.1+ is required to run the current version of Intersect.
I would suggest downloading and installing .Net Framework 4.6.1 or greater and see if that fixes the issue.
I just don't see how it would be working for you in the morning then not in the afternoon, that would suggest something has changed on your PC.