Xarg & Wget stops working after about an hour

[Jake1]

Running your script with Cygwin on Windows XP with Dual Core and 4GB Ram

I run the script with ./crawl.sh urlfile.txt 50

I am trying to trawl through 4GB of URL

The Bash shell seems to stop after about an hour and the downloads stop even though its only 2% through the URL list

Any ideas at what could be wrong?

Many Thanks