Windows File Sharing Fails with Error Code -6602

For the past couple days I’ve been unable to mount my Windows XP Professional Version 2002 SP3 home server from my Mac OS X 10.5.5.  On the Mac I would get the error “Sorry the operation could not be completed because an unexpected error occurred. (Error code -6602)”.  When I tried the share from another XP system I got, “\\totoro\Documents is not accessible. You might not have permission to use this network resource.  Contact the administrator of this server to find out if you have access permissions.  Not enough server storage is available to process this command.”  A Google search didn’t produce any useful results.
I then remembered to check the XP Event Viewer system log.  In there I found a clue, “The server’s configuration parameter “irpstacksize” is too small for the server to use a local device.  Please increase the value of this parameter.”  Clicking on the accompanied link took me to a Microsoft page that said to change the registry value HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters\IrpStackSize to the default 15 (decimal).  My system didn’t even have the DWORD value so I had to create it.  A restart is necessary after working with this value.

After I rebooted I could connect to the shares again normally.