In tip 1705, we learned that PING uses ICMP packets and may not be affected by circumstances that would cause a NET USE to a NetBIOS resource to fail.
Here are some troubleshooting steps to resolve the problem:
- If a router is between you and the resource, insure that TCP port 139 is enabled.
- If a router is between you and the resource, make sure it can pass large packet sizes. PING only send 74 bytes of data. To test for a packet size problem:
PING <computername> -l 4048
PING <computername> -l 3036
PING <computername> -l 2024
PING <computername> -l 1012
You should NOT need to adjust the MTU,
unless EnablePMTUDiscovery is disabled.
You may also wish to look at
EnablePMTUBHDetect.
You can adjust the MTU at
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\<AdapterName#>\Parameters\Tcpip
by adding a value name of MTU, as a type REG_DWORD,
and setting the data value to a number between 0 and 0xFFFFFFFF.
Datagrams larger than the Maximum Transmission Unit are divided in fragments.
- Check to make sure that the Server Service is started on the destination computer (Control Panel / Services).
- Make sure that the destination computer is not hung (it may still respond to a PING).
- Make sure that there are available licenses on the destination computer.
- Make sure that the drive letter is not already in use. Use NET USE <Drive:> /delete.
- Make sure that if a HOSTS or LMHOST file is used for name resolution, that your network is not timing out.
