Fix RPC_S_INCOMPLETE_NAME 0X000006DB Error

Quick answer

Run nbtstat -c to check cached NetBIOS entries. If you see an incomplete name (missing 20th character or service type), flush it with nbtstat -R and then ipconfig /flushdns. Restart the Server service and retry. If that doesn't work, check your LMHOSTS file for truncated names.

What's going on here?

This error usually pops up when Windows tries to connect to a remote server—maybe a file share, DFS namespace, or a mapped drive—and the RPC endpoint mapper can't find the full server name. Back in the wild, I had a client with a Windows Server 2016 file server that would randomly throw this for a handful of workstations. The common thread? They were using WINS, and one of the WINS entries had a truncated name (15 chars max for NetBIOS). The server's actual NetBIOS name was 16 characters—Windows cut it off at 15, but the client expected 16. Boom, 0x000006DB.

Microsoft's KB articles call this a "name resolution failure" but that's vague. The real trigger is a mismatch between what the client thinks the name is (complete with the 16th byte for service type) and what the server or WINS database reports. Happens often with multi-homed servers or after a DNS migration.

Fix steps

Check the NetBIOS cache. Open Command Prompt as admin. Type nbtstat -c. Look for the remote server's name. If the name column shows something like SERVERNAME <00> but it's only 15 characters, you've found the problem.
Flush the cache. Run nbtstat -R (capital R). Then ipconfig /flushdns. This clears both DNS and NetBIOS entries.
Restart services. Run net stop server, then net start server. Also restart the Workstation service: net stop workstation and net start workstation. These services hold RPC mappings.
Test the connection. Try mapping the drive again: net use x: \\servername\share. If it works, the error was cache-driven. If not, move to the fix below.

Alternative fix: LMHOSTS or WINS

If flushing didn't do it, the issue is probably in your LMHOSTS file or WINS server. Here's the quick check:

Open C:\Windows\System32\drivers\etc\lmhosts in Notepad (run as admin). Look for the server entry. If the name is over 15 characters, you need to add the 16th byte (service type) as a comment. Example: 192.168.1.100 SERVERNAME #PRE #DOM:domain — but if the name is longer, you have to truncate it to 15 chars maximum. Or better yet, use the IP address directly in the connection.
If you're using WINS, go to the server's WINS console. Check the active registrations. If the server shows up with a truncated name, right-click and delete it, then restart the server's NetBIOS service (net stop lmhosts, net start lmhosts) to re-register.
For DFS users: this error is common with multi-site namespaces. Switch to FQDN names: \\server.domain.com\share instead of \\server\share. DNS handles long names better.

Prevention tip

Keep your NetBIOS names under 15 characters. Seriously. If you can rename a server to 15 chars or less, do it. Also, drop WINS if you're on a pure Active Directory network—DNS alone handles name resolution without this truncation headache. I've seen this error disappear for weeks after migrating away from WINS.

One last thing: if you're still seeing this error after all that, check the server's registry at HKLM\SYSTEM\CurrentControlSet\Services\NetBT\Parameters. Look for NodeType set to 4 (mixed mode). That can cause incomplete names if WINS is unreachable. Change it to 2 (point-to-point) if you rely on a WINS server, or 1 (broadcast) if you don't. Reboot after. That'll force consistent name resolution.