I need to run a script on our network to determine if we have machines in the field with a blank password. Does anyone know how I can achieve this?

you mean you want to look if yur vulnerable??? then use the ipcscan and check yur ips

depending on how many computers you are scanning.

if you need to scan alot of boxes i would run "enum.exe" to get usernames.
then use NAT to check for null or weak passwords.

if you only need to scan a few i would try the C.I.S. scanner and disable the modes you don't need

if you use windows, maybe MS Baseline Security Analyzer can satisfy your need

I suggest GFI LANGuard. Its has the function to establish 'null sessions'. Check it out .... http://www.gfi.com/lannetscan/

wow, lots of great ideas. Thanks everyone! I'll post back the solution I used when I get everything working

So what solution did u use?

Or still not wotking? :|

î think MS Baseline Security Analyzer is the best solution, then u would also see if u need important updates...

Are u using a MS Windows domaincontroller? cuz else u can just use pwdump2 in combination with l0pthcrack.

pwdump2 can dump the password hashes.
and l0pthcrack cracks them.

If u r not using aan MS Windows domaincontroller use can scan ur networkt with ipcscan.exe