A user can't sign in. You reset their password. Still can't sign in. 😩
Before you go further down the rabbit hole, look at the clock in the corner of their screen. Seriously. A wrong time is one of the sneakiest causes of "nothing makes sense" tickets.
🤔 Why the clock matters
On a Windows domain, sign-in uses Kerberos, and Kerberos tickets are time-stamped. By default, if a computer's clock is more than 5 minutes off from the domain controller, authentication fails. The error messages rarely say "your clock is wrong," so it looks like a password or account problem.
A wrong clock can also break HTTPS: certificates have "valid from" and "valid to" dates, so a PC living in the wrong year can throw certificate errors on perfectly good websites.
1️⃣ Check the time AND the time zone
Compare the PC's clock with your phone. Then check the time zone in Settings > Time & language > Date & time. A laptop that traveled (or a fresh install) can have the right "local" time with the wrong time zone, which still adds up to the wrong actual time.
2️⃣ See where the PC gets its time
Open Command Prompt or PowerShell and run:
w32tm /query /status
Look at Source and Last Successful Sync Time. A domain-joined PC normally syncs from a domain controller. A home or workgroup PC usually syncs from an internet time server like time.windows.com. If the source says Local CMOS Clock or the last sync was ages ago, you've found your suspect. 🔍
3️⃣ Force a resync
From an elevated (Run as administrator) prompt:
w32tm /resync
If it complains that the time service isn't running, start it first:
net start w32time
w32tm /resync
Now try the sign-in again. ✅
🔋 Then ask: why did it drift?
Fixing the time is great, but find the cause so the ticket doesn't come back:
- Dead CMOS battery on an older desktop: the time resets after every power loss.
- PC offline for a long time and can't reach a time source.
- Wrong time zone set manually.
Note it in the ticket so the next tech knows the history. 📝
🎯 The takeaway
When sign-ins or certificates fail for no clear reason, spend 10 seconds on the clock before you spend 30 minutes on the account.
What's the strangest problem you've ever fixed just by correcting the time? 👇
