RSE cache problems

I have been having some problems the last few days with source changes 
being saved to the RSE cache, but not to the i5.  I was digging through 
the archives and found a post about clearing the cache from the 
Preferences dialogue, and I decided to try that.  I got an error message 
"RSEF6102W: Unable to synchronize cache changes to host.  Operation 
cancelled."  I tried restarting the workbench, then clearing the cache 
again, but I got the same error.  I then rebooted my PC and tried again, 
same error.  There don't seem to be any rogue RSE communication jobs 
running.  The only WDSC related job I could see was the debug job 
QB5ROUTER.  Does anyone have any suggestions of how I can clear the cache? 
 Is it safe to just delete the cached files manually?

I can't seem to find the previous discussions about which caching options 
should be checked or unchecked in the Preferences.  Has anyone had this 
problem and solved it (without any black magic or sacrifices)?  It seems 
to be very much a phase of the moon thing for me.

TIA,
Adam

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