I have two machines running Windows 7 pro in a workgroup. PC A RDP's to PC B over port 3398 and has been working for months. As of this week the connection has failed access denied over port 3398. Nothing has changed as far as I know.
In your OP you sited port 3398. I don't know if that is a typo (if so you typo'd it twice). The default listening port for RDP is 3389 not 3398 and is controlled here in the Windows Registry;
(left pane) HKEY_LOCAL_MACHINE\SYSTEM\CurrentContolSet\Control\Terminal Server\WinStations\RDP-Tcp
(right pane) PortNumber REG_DWORD 0x00000d3d (3389)
SOURCE: How to change the listening port for Remote Desktop
If for some reason you have changed the default port number on either machine, it needs to be reflected in you mstsc call to that machine like;
Also you might want to review this regarding the use of port 3398 and perhaps choose another higher port number if it is your intent to use something other than the default port number, something like 8888 or 8886 etc., I've used both successfully in the past.
Good to hear that you were able to resolve your problem and thanks for posting back and updating your thread.
Sounds like it may have been a problem with the NetBIOS cache on one of or both machine(s). The NetBIOS mechanism attempts to resolve friendly names (computer host names) to IP Adresses and can often take some time to refresh itself with up to date accurate information. Sometimes you can use the ping command to force an update by pinging the ip address (using the -a switch to determine the host name) and then the host name. You can then view the local machines NetBIOS name cache content by typing
at the command prompt
Usually using IP addresses instead of host names when connecting through RDP is more reliable and using static IP address assignments is even more reliable yet.
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