Completely un-usable while the overwrite is being done, best bet is to set it to do them automatically every night/week/month (Whichever is good enough for your location)
CWIS > Properties > Security > Image Overwrite Security
When doing an image overwire on a xerox 4265 is the printer still useable or is it out of commission for the 30 to 120 minutes that it is being run??
Thanks in advance