Nested folders = 'not responding' error?

As a matter of habit I use nested folders for storage.

Example: My Documents (folder)
My Received Files (folder)
Security (folder)
SpyBot (folder)
Program files
Lavasoft (folder)
Program files

What I've recently noticed (and I don't remember this being the case in the
past) is that if I attempt to go deeper than the second level of the nesting
over my network the third folder will give a 'not responding' error. Is this
normal? If not, how can I correct the problem?