Slow Explorer

[Fredrated]

Browsing for a file has suddenly become a pain.
In Access, Word, Excel, when I click on 'file open' the system seems to hang
for about a minute before the drive - file list displays.

The system is doing something during this time; for example, if I try to
open windows explorer after clicking 'file open' in Access, win explorer also
takes a minute or so before listing the drive - filelist.

I am told we got a security update this weekend, could that have done
something bad to my system?

Any thoughts are greatly appreciated

Fred