0X0000078B Context Expired – Quick Fix & Why

That 0X0000078B error pops up at the worst time — maybe when you're trying to access a network share, run a remote management tool, or connect to a database. The message says the context has expired and can no longer be used. What's actually happening here is that a security token or authentication handle your app was holding onto got invalidated by the system. The fix isn't reinstalling Windows. It's much simpler.

The Direct Fix

1. Press Win + R, type services.msc, and hit Enter.
2. Find Netlogon in the list. Right-click it and select Restart.
3. Next, open an elevated Command Prompt — right-click the Start button and choose Terminal (Admin).
4. Type klist purge and press Enter. This clears all cached Kerberos tickets.
5. Type gpupdate /force and press Enter to refresh Group Policy.
6. Reboot the machine once.

That's it. After the reboot, the error should be gone. If you were in the middle of something, close and reopen the app that showed the error.

Why This Works

The 0x0000078B error is a STATUS_CONTEXT_EXPIRED status code from the Windows kernel. It means the authentication context a process was using — usually a Kerberos ticket or an LSASS (Local Security Authority Subsystem Service) session — got invalidated. This can happen for a few reasons:

• The Kerberos ticket lifetime expired (default is 10 hours, but some apps check earlier).
• The LSASS process crashed or was restarted, which kills all active security contexts.
• System time drifted out of sync with the domain controller — Kerberos is obsessive about time sync, more than 5 minutes off kills tickets.

Restarting Netlogon forces the service to re-establish trust with the domain controller and regenerate the machine's secure channel. That's the service that handles logon authentication and keeps the session alive. klist purge wipes out any stale or corrupted cached tickets that Windows might try to reuse. Without that purge, Netlogon restart might reissue a fresh ticket, but the app could still grab a stale one from the cache. The gpupdate /force ensures Group Policy settings applied correctly after the re-authentication, especially if you're in a domain environment where policies depend on a valid secure channel.

The reboot is belt-and-suspenders — it forces every application to re-request a fresh context. Honestly, most of the time step 2 alone (klist purge) fixes it. But when it doesn't, it's usually because Netlogon was in a bad state.

Less Common Variations of This Issue

1. The LSASS Crash Variant

Sometimes the error appears with a reference to LSASS or LSASS.exe crashing in the System event log (Event ID 1000 or 1012). In that case, restarting Netlogon won't help because LSASS itself is corrupted. Open an admin command prompt and run sfc /scannow followed by DISM /online /cleanup-image /restorehealth. If that doesn't fix it, check the memory — bad RAM can corrupt LSASS in flight. MemTest86 is free and runs from a USB stick.

2. The RPC Context Expired Variant

With RPC (Remote Procedure Call) apps — think remote WMI queries, SCCM client actions, or Exchange management tools — the error might say “The context has expired” without the 0x0000078B code explicitly shown. Check the Application event log for Event ID 7031 or 7034 for RPC-related services stopping. Restart the RPC service (net start RpcSs from admin prompt), then restart your app. If it keeps happening, the RPC endpoint mapper might be stuck; reboot the machine.

3. The Azure AD / Modern Auth Variant

If you're on Windows 10 or 11 with Microsoft 365 apps (Outlook, Teams, OneDrive) that use modern authentication, the error might manifest as a generic “Credentials needed” prompt that loops. The underlying cause is the same — a token expired. But the fix is different: close the app, open Credential Manager (Control Panel > User Accounts > Credential Manager), remove any entries under Windows Credentials that mention your Microsoft account or the app name (like “MicrosoftTeams” or “OneDrive Cached Credential”), then reopen the app. It'll re-authenticate fresh.

4. The Time Sync Variant

This one's sneaky. If the error appears only when connecting to a specific server or service, run w32tm /query /status in a command prompt. If the source shows something other than your domain controller (or the time is off by more than 5 minutes), run w32tm /resync to force a time sync. On a domain-joined machine, you can also restart the Windows Time service (net stop w32time && net start w32time). Kerberos dies instantly if the clock skew exceeds 5 minutes.

Prevention

This error tends to happen more when you're doing things that invalidate active tokens — like changing your domain password, joining or leaving a domain, or after a network outage that dropped the connection to the domain controller. You can't prevent all of those, but you can minimize the annoyance:

• Keep your system time synced automatically with the domain controller or a reliable NTP source. Don't let it drift.
• If you run long-lived scripts or scheduled tasks that authenticate over the network, consider using service accounts or managed service accounts with longer token lifetimes. Standard user tokens expire after 10 hours by default.
• For apps that connect to remote resources, running klist purge before a long session or before starting a critical operation is a cheap insurance policy. You can even script it to run at login.
• If you're an admin managing many machines, push a scheduled task via Group Policy that runs klist purge and restarts Netlogon daily at 3 AM. It's brutal but effective for preventing stale context errors during business hours.

Skip reinstalling Windows for this one. It's a token hiccup, not a system meltdown. The fix takes two minutes.