Strange error msg when plotting a graphics

Dear R-Users

I have come across the error that apparently has nothing to do with command itself.  Here is the error

(w - matrix (or vector) e testXaxis - dates).

plot(data.frame(testXaxis,w),col="blue",ylab="Q, [m3/s]",xlab="Data",

+      main="Free-run - Modelo NARX MISO - Test Data")
Error in gzfile(file, "wb") : cannot open the connection
In addition: Warning message:
In gzfile(file, "wb") :
  cannot open compressed file '/Users/eduardo/.rstudio-desktop/graphics/0540fa66-727a-4f8f-a1b5-f6501e96a393.snapshot', probable reason 'No such file or directory'
Graphics error: Error in gzfile(file, "wb") : cannot open the connection

The error did not stop the graphics of being plotted.

What could be wrong?

Many thanks

Ed