I am running Service Desk 4.5 SP18 and have one user that recieves a error when trying to open or attach a attachment to a Service Call. We have re-installed Service Desk client and java and also removed the "Service Desk" folder under documents and settings with no like. The error is "Error when put file C:\Documents and Settings\yourname\Desktop\Kr450_admin_DocumentList_06.08.2006_10.27.01_AM.xls to attachments server: java.io.InteruptedIOException:Accept timed out"
We had a similar problem with attachments in SP18, although the error message may not have been the same. In our case the user had the Windows XP firewall running. When they disabled the XP firewall, the error went away.
I experienced something similar with a small number of clients. What we found was this happened when they tried to attacht files over a certain size - generaly bitmaps of user screenshots which were over a few MB's.
Workaround was to ask users for JPEGS instaed with attached with no problem.
Still investigaing why this happens. Does this happen to you for certain sze files?