Box access results in errors

For some reason, I cannot access any box folder that I previously was able to last week.  I get one of the following errors:

• Oops! We can't seem to find the page you're looking for.
• This shared file or folder link has been removed or is unavailable to you.

I can get to my own box folder, but nothing else.  Any ideas as to what is going on with my account?
 

Thanks,

Keith