Fix 0X0000099E: Invalid connection ID in Windows

Cause #1: Orphaned mapped drive in Windows

This error pops up when Windows tries to use a network connection ID that's been deleted or disconnected — think of it as a ghost drive. You'll see it most often in scripts, batch files, or when running commands like net use on a drive letter that was mapped, then the remote share was removed, but Windows still thinks the connection exists.

Had a client last month — small law firm — kept getting this error every time their backup script ran. The script tried to delete and re-map a drive, but the old connection never fully cleared. The fix? Kill the ghost first.

How to find and remove the orphaned connection

Open Command Prompt as admin and run:

net use

Look for the drive letter or connection listed. If you see a drive with "Disconnected" or one that shows no status at all, that's your culprit. Remove it with:

net use X: /delete

Replace X: with the actual drive letter. If the delete fails with the same error, force it:

net use * /delete /y

That nukes every cached network connection. Then re-map the drive fresh:

net use X: \\server\share /persistent:yes

Test your script or action again — it should work now.

Why this works: Windows stores connection IDs in the registry under HKEY_CURRENT_USER\Network. If the remote share goes away but the registry entry stays, you get 0X0000099E. Deleting the connection cleans both the live list and the reg key.

Cause #2: Stale persistent drive mapping in the registry

Sometimes net use /delete doesn't fully remove the entry — especially if Windows crashed or the drive was disconnected unexpectedly. The registry still holds the old connection, and any new attempt to map the same drive letter fails with this error.

Registry cleanup (advanced users only)

Back up your registry first. Then navigate to:

HKEY_CURRENT_USER\Network

You'll see subkeys named after drive letters (e.g., Z, Y). Delete the subkey for the problem drive letter. Close regedit, restart File Explorer, and re-map the drive from scratch.

I've seen this a lot on Windows 10 21H2 builds — the registry entry survives a reboot but the connection itself is gone. Manual reg deletion is the only fix.

Cause #3: Script or application caching a stale connection handle

If the error comes from a specific app or script — not from net use directly — the program might have opened a connection, then the network path went offline, and the app still holds the old handle. This is common with older backup software (looking at you, Backup Exec) or custom PowerShell scripts that use New-PSDrive.

Fix: Restart the app or script, then re-establish the connection

Close the application completely. In Task Manager, kill any background processes tied to it. Then re-run the script or app fresh. If it's a PowerShell script, restructure it to check if the drive exists first:

$drive = Get-PSDrive -Name X -ErrorAction SilentlyContinue
if ($drive) {
    Remove-PSDrive -Name X -Force
}
New-PSDrive -Name X -PSProvider FileSystem -Root \\server\share -Persist

For batch scripts, add a net use X: /delete at the very start, before any net use command that maps the drive. This clears any leftover handle before creating a new one.

Quick-reference summary