PC Windows Update Stuck at 0%, 99% or 100%: How Long to Wait, Then What
In plain English: If Windows Update has sat at 0%, 99%, or 100% for a while, it has not necessarily failed. Windows often works for a long stretch without moving the percentage, especially during a large monthly or feature update.
First safe step: Look and listen for work in progress before you decide. If the PC still shows signs of work, leave it alone.
If Windows Update has sat at 0%, 99%, or 100% for a while, it has not necessarily failed. Windows often works for a long stretch without moving the percentage, especially during a large monthly or feature update.
A slow update still shows signs of life, such as disk activity, a spinning circle, or a fan running. A frozen update shows none of that for a long time, and the screen does not change at all.
This page gives honest wait times based on your PC's age and whether it uses a hard drive or an SSD. It also marks the point where restarting is safe, and links you to the fix for any error code you find, instead of repeating those fix steps here.
Part of the Windows Update Problems: Stuck, Failed and Slow Updates Fixed Safely series, the pillar guide for this cluster.
Is it really stuck, or just slow?
Is it really stuck, or just slow?
A percentage that stops moving does not by itself mean Windows Update has failed. Updates often pause at 0%, 99%, or 100% while large files are checked or prepared in the background. If the PC still shows signs of work, leave it alone. It is frozen only if nothing changes for the full wait time below.
That number can stop in three different places, and the place matters for what you can check. It may stop while downloading in Settings, while installing in Settings, or on the blue or black Working on updates screen that fills the whole screen after a restart. The first two leave Settings open. The third leaves you with almost nothing to click, which is normal.
Look and listen for work in progress before you decide. A flashing drive light, a fan that starts, stops, and starts again, a mouse pointer that still moves when you touch the mouse, a spinning circle, or wording or numbers that change, even slowly, all mean the update is still going. No single sign has to be present the whole time.
Use this plain rule, and do not judge by the percentage alone. If any sign of activity is there, the update is slow, so wait and check again later. It counts as frozen only when the screen, wording, and numbers stay exactly the same and there is no drive light, fan, spinning circle, or mouse activity for the full wait time given for your PC in the next section.
How long to wait at 0%, 99% and 100%
Age matters less than drive type. A hard drive moves files much more slowly than a solid state drive, so the same update can take much longer on an older PC. The ranges below give a wait time and a ceiling for each type of PC.
A normal monthly update is the smaller, regular set of fixes. Newer PC, solid state drive (SSD): 30 minutes to 1 hour. Ceiling: 1 hour. Older PC, solid state drive (SSD): 1 to 2 hours. Ceiling: 2 hours. Older PC, hard drive (HDD): 2 to 3 hours. Ceiling: 3 hours.
A feature update installs a large new version of Windows, so it takes longer on every PC. Newer PC, solid state drive (SSD): 1 to 2 hours. Ceiling: 2 hours. Older PC, solid state drive (SSD): 2 to 3 hours. Ceiling: 3 hours. Older PC, hard drive (HDD): 3 to 4 hours. Ceiling: 4 hours.
If you do not know your drive type, use the hard drive times. That errs on the side of patience and avoids cutting off a slow but working update too soon. A PC bought in the last few years will usually have a solid state drive, but age alone is not a sure guide.
The percentage can mislead you at both ends. At 0%, the download has often barely started, or Windows is checking what the PC needs before files move, so give it the full wait for your PC. At 99% or 100%, the download may be done while final setup, file checks, and cleanup still run in the background.
Pick the row that matches your PC and use its ceiling, even if the percentage looks close to done. Once that time passes with no change, waiting all day rarely helps. Move on to the next section, which covers when a restart is safe.
What to do while you wait, and what not to do
Keep the PC plugged into power for the whole wait. If it is a laptop, do not rely on the battery alone, and make sure the charger stays connected. Keep the PC connected to the internet too, on Wi-Fi or a wired connection, so any part still downloading can finish.
Leave the PC alone while it works. Check the screen now and then for a changed percentage, new wording, or a spinning circle, but do not open other programs or try to use the PC in the meantime. Waiting is the work at this stage.
Write down the time you first noticed the percentage had stopped, the exact percentage, and the exact wording on the screen. If a phone is handy, take a clear photo of the screen as well. You will want those details later, and they help anyone you ask for help.
Do not hold the power button, pull the plug, or remove the battery while an update is in progress. Do not run updater, cleaner, or driver tools during the wait either. Stopping power or changing files at the same time can turn a slow update into a failed one.
When restarting is safe, and how to do it
The safest point to restart is while you are still on the desktop in Settings, before any restart screen has begun. At that point a normal restart cannot hurt your files, and you can still open Start in the usual way. Windows will either pick the update up again after the restart or roll it back to how it was, and your documents and photos stay as they were.
Before you restart, work through this check in order. First, the wait time for your PC in the table above has fully passed. Second, the percentage and the wording on screen have not changed at all during that time. Third, there is no drive activity, no flashing light, and no sign the PC is still working. All three must be true together. If one fails, wait and check again.
When all three checks pass and you are on the desktop, restart the normal way. Select Start, then Power, then Restart, and let the PC close Settings and restart on its own. Do not use Shut down for this, and do not hold the power button. Then leave the PC alone while it starts up again, which may take several minutes.
The Working on updates screen is different. Windows is already changing system files there, so wait much longer than you would in Settings. Only if every check above is met, hold the power button until the screen goes dark, press it once to restart, and leave the PC alone to recover. Recovery can look slow at first. If Undoing changes appears, see our guide to that screen.
After the restart, check what actually installed
Once you are back at the desktop and signed in, give the PC 10 to 15 minutes to settle before you check anything. Windows may still be finishing work in the background. A check made too soon can show the old percentage or an incomplete result.
After that wait, open Settings and go to Windows Update. Check the message on that page first, then open Update history and look for the update you were waiting for. Keep this to a short check of the result, so you know where you stand after the restart.
One of three results should be clear. The update installed and is listed as complete, it failed and shows an error code, or Windows offers the same update again as if nothing happened. Each result points to a different next step, so base your next move on what the page says.
Before you move on, write down the KB number shown next to the update and any error code exactly as it appears. Keep capital letters and numbers as shown. If the update installed, stop here, because no further fix is needed for that update.
If it gets stuck again, check these causes in order
If it gets stuck again, compare the two stalls before you try anything else. Note the percentage where it stopped and the KB number of the update. If it stops at the same percentage on the same KB update, that pattern points to the update itself. A stall at a different point is less clear, so give it the full wait time for your PC.
Check the simple causes first, in this order. One, confirm the PC is still online, with Wi-Fi connected or a cable plugged in. Two, check free space on the Windows drive. Three, run Check for updates once more in Settings and let it finish on its own. A lost connection can hold a download at 0%, and a nearly full drive can stop setup from finishing.
Then follow what you found. If Update history shows an error code, look up that exact code and follow the fix on its page. Use the code exactly as shown, since a similar code can mean a different problem. If the drive is low on space, follow the page on freeing space on your drive, then try the update again.
If the same KB update keeps being offered, or it stalls again after the checks above, follow the page on a Windows update that keeps repeating. If an update did install and the PC has worked badly since then, follow the page on uninstalling a bad Windows update. That order stops you restarting again and again while the same cause is still there.
Conclusion
A percentage that will not move is frustrating because nothing on the screen tells you whether to wait or act. Time and activity give you that answer. If both have run out, a restart is a decision you can make with confidence, not a gamble you take because you ran out of patience.
Whatever the update history shows next is your starting point, not a guess. Follow the result you actually got, write down any code exactly as it appears, and use the linked page for that problem. One clear next step will do more than trying several fixes at once.