Error in lazyLoadDBfetch

R was working fine for a while.  However, now after I get some data from the 
web and try to "write", "write.table" or "save.image", I get this error:

Error in lazyLoadDBfetch(key, datafile, compressed, envhook) : file open 
failed

I may have downloaded additional packages in between the time it worked, and 
now when it doesn't work, but other than that I cannot think of any change 
that would cause this error.

Any help appreciated -- thanks!

atm