"Not enough server storage is available to process this command."
"Not enough memory to complete transaction. Close some applications and retry."
These error messages can indicate an incorrect IRPStackSize on the remote computer (the one you are trying to access over the network). In the remote computer, open the event log and check for event ID 2011. If this is present, it may indicate this particular issue. To repair it, you need to set the IRPStackSize parameter in the registry back to its default value of 15.
Check for the presence of a value named IRPStackSize. If it doesn't exist, create it as type DWORD and, with base set to decimal, enter the value 15. Exit from the registry and reboot the computer.
Some AntiVirus programs are guilty of altering this setting and causing the problem.
Also have a look at this Microsoft Knowledge Base article which applies to XP too:
Antivirus Software May Cause Event ID 2011 (Q177078)