'Send To' - Large Files - Error

I use ‘send to’ to backup a large file (my documents) between two PC’s.  They are both running XP SP3.  Since installing NIS2009 on them, the ‘send to’ command errors out after a short time (1-2 minutes).  I’ve tried changing the ‘trust’ level between the two PC’s and it did not help.  Any thoughts on what is happening / how to make it work?  Thanks.