Windows
Mapped drives disconnected when the Windows file server hit its connection limit
Shared drives were disconnecting because the Windows server could only handle 20 active connections at once and idle connections were holding slots. The idle connection release time was shortened from 15 minutes to 5 minutes to reduce the disconnects during normal use.
Killed once by someone from XL.net, on 2026-10-23.
Affects
Versions
- Windows
Hardware
- Windows file server
What you see
- Mapped network drives showed as disconnected.
- Users were unable to reconnect when the server had reached its active connection limit.
Why it happens
Likely The server reached its built-in 20-connection limit, and idle connections were staying open long enough to block new drive connections.
When it shows up
A Windows file server with shared folders reaches its active connection limit and mapped drives disconnect for users or devices.
You are in this case if:
- The server is limited to 20 active connections.
- Idle share connections remain open for about 15 minutes before release.
1 fix below
The steps that killed it
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Keeping it away
- Keep idle share connections from holding slots too long on the server.
- Watch for the 20-connection ceiling on this Windows file server setup.
Someone from XL.net killed this on a Windows computer on 2026-10-23. It is written up from that one repair, so it cites no outside page.