Finder Crashing: Not Google Drive

Question

My finder keeps crashing. It happens when I open a file through Rhinocerous Wenatchee, but not if I open it through the desktop. It also crashes when saving a file in Photoshop, then leaving Photoshop unresponsive and needing to be force quit.
I do not have Google Drive, and could not find com.apple.finder.plist in the Finder>Prefrences folder, so those aren't the problems.
I also reinstalled Mavericks today, but that did'nt help either.
I installed Mavericks weeks ago when it came out, but htis problem only started a couple of days ago. Computer has been running rather slowly of late however.
Thanks for any sugggestions in advance.
Model Name:          iMac
  Model Identifier:          iMac9,1
  Processor Name:          Intel Core 2 Duo
  Processor Speed:          3.06 GHz
  Number of Processors:          1
  Total Number of Cores:          2
  L2 Cache:          6 MB
  Memory:          4 GB
  Bus Speed:          1.07 GHz
  Boot ROM Version:          IM91.008D.B08
  SMC Version (system):          1.37f3
  Serial Number (system):          W89070MB250
  Hardware UUID:          B4647A41-AC60-56AD-8D5D-9AF739492AEA

Answer 1

If this were happening to me, I would try to narrow down the source of the problem by seeing if the problem persists by (1) logging in as a different user (e.g., Guest) and (2) starting up in Safe Mode.  (1) Helps identify problems specific to your account, e.g., login items, preference files, etc.,  (2) helps identify third-party system-level conflicts.
If you can get to it, you might try trashing Finder preferences at ~/Library/Preferences/com.apple.finder.plist.  You could do this with Terminal. Also, try dumping Sophos.