I've had this problem in the past, what is happening is that when the workstation is not logged in, or another user is logged in, the K: share is not mapped. There is a way to force a share to always be mapped, even when nobody is logged in. I remember how this is done, but mabey someone else will. I'll also try doing a search to find what needed to be done.

UPDATE: I remembered what is was, it wasn't the network path. I had to wrap the perl script with a batch file. This was the batch file:

d:\perl\bin\perl.exe c:\path\script.pl
[download]

Using this with the run as checked the script would work.