A Windows 11 upgrade is supposed to feel exciting, but when it gets stuck at 99%, it can quickly become stressful. Many users think the PC is frozen, the update is broken, or the system will never boot again. The good news is that a Windows 11 upgrade stuck at 99% is a common issue, and in many cases, it can be fixed without losing your data.
In this guide, you will learn why Windows 11 upgrades get stuck at 99%, what you should do first, and the safest ways to fix the problem step-by-step. This article is written in simple language with limited bullet points only where needed.
Why Is Windows 11 Upgrade Stuck at 99%?
When the upgrade reaches 99%, Windows is usually finishing the last tasks. These final tasks can take time because Windows may be doing background work such as:
Finalizing system files and applying settings
Installing drivers and cleaning up temporary upgrade data
Migrating old settings and apps to the new version
Completing “first boot” configuration tasks
Creating restore points and preparing update rollback safety
Sometimes it looks stuck, but it is actually working silently. Other times, it is truly stuck because something went wrong.
First: How Long Should You Wait at 99%?
Before you try to fix anything, you should allow Windows some time. In many cases, Windows can stay at 99% for a long time, especially on slower systems or laptops with HDD storage.
A safe waiting time depends on your PC type:
On SSD-based PCs, you can wait around 30–60 minutes
On older HDD PCs, it can take 1–3 hours
On very old systems with low RAM, it may even take longer
If your PC shows signs of activity like a blinking drive light, fan noise, or the mouse still moves, it’s usually better to wait a little longer.
However, if it has been stuck at 99% for many hours with no change, then it’s time to fix it.
Important Warning Before You Start Fixing
When Windows is upgrading, forcing a shutdown can sometimes cause boot problems. That’s why you should do the safest steps first before taking the aggressive options.
Also, if this is a laptop, keep it connected to power. A sudden battery drain during upgrade can cause system corruption.
Step 1: Check If Windows Is Actually Frozen or Still Working
Even if the screen shows 99%, Windows might still be processing tasks.
Here are simple things you can check:
Try moving the mouse pointer
Press Caps Lock and see if the keyboard light reacts
Listen for fan changes or hard disk sound
Check if the update percentage changes after 10–15 minutes
If you notice any activity, wait a bit longer. If everything is completely unresponsive, continue to the next step.
Step 2: Disconnect Unnecessary Devices (Very Important)
A common reason Windows upgrades get stuck is driver problems or conflicts caused by connected accessories.
Disconnect everything except essentials:
USB drives and external hard disks
Printers and scanners
Wireless dongles
Game controllers
Extra monitors (if not needed)
Webcams and external microphones
Keep only:
Keyboard and mouse
Power cable
Internet connection (optional, but helpful)
After disconnecting, wait 10–20 minutes and see if it moves forward.
Step 3: Restart the PC (Safe Method)
If the upgrade has been stuck at 99% for a long time, you may need to restart. A restart sounds scary, but Windows is designed to recover from interrupted updates in many cases.
Here is the safest restart method:
Hold the power button for about 10 seconds until the PC turns off
Wait 15–20 seconds
Turn it on again
When the PC starts again, Windows may show:
“Working on updates”
“Undoing changes made to your computer”
“Diagnosing your PC”
“Attempting repairs”
This is normal. Let it complete the process. Many times, the system will boot successfully after this.
Step 4: Let Windows Roll Back If It Starts Rolling Back
Sometimes after the forced restart, Windows automatically rolls back to the previous version. This can feel disappointing, but it is actually a safety feature.
If you see messages like:
“Undoing changes”
“We couldn’t install Windows 11”
“Restoring your previous version of Windows”
Do not interrupt it. Once rollback is done, Windows will boot normally and you can retry the upgrade after fixing the issue.
Step 5: Use Startup Repair (If Windows Won’t Boot)
If Windows refuses to boot after the restart, you should enter the Windows Recovery Environment.
To open recovery mode:
Turn your PC on
As soon as the Windows logo appears, hold the power button to shut down
Repeat this process 2–3 times
Windows will open Automatic Repair mode
Now follow:
Click Advanced options
Choose Troubleshoot
Select Advanced options
Click Startup Repair
Startup Repair will attempt to fix boot-related upgrade problems automatically.
Step 6: Boot into Safe Mode and Remove Upgrade Blockers
If Windows boots but the upgrade keeps failing or gets stuck again, Safe Mode can help you remove common blockers.
To enter Safe Mode:
Open Settings
Go to System
Click Recovery
Under Advanced startup, choose Restart now
Select Troubleshoot > Advanced options > Startup Settings > Restart
Press 4 for Safe Mode or 5 for Safe Mode with Networking
In Safe Mode, try these quick fixes:
Uninstall third-party antivirus
Disable VPN or network filtering tools
Remove unused drivers or old device tools
Uninstall heavy system tweaking apps
Antivirus and security tools are a very common reason upgrades freeze near the final stage.
Step 7: Free Up Space on Your C Drive
Windows upgrades need a lot of free space. Even if you had enough space to begin, the final stage may require additional space for cleanup and installation.
A safe target is:
At least 25–30 GB free (minimum)
40 GB free is even better
To clean storage safely:
Open Settings
Go to System > Storage
Click Temporary files
Select safe items like temporary data and delivery optimization files
Click Remove files
Avoid deleting Downloads if you have important files there.
Step 8: Run Windows Update Troubleshooter
If your upgrade was happening through Windows Update, the update service may be stuck.
To run the troubleshooter:
Open Settings
Go to System > Troubleshoot
Click Other troubleshooters
Run Windows Update troubleshooter
This tool can fix broken update components automatically.
Step 9: Reset Windows Update Components (Manual Fix)
If the upgrade keeps freezing at 99%, resetting update components can solve the issue.
Follow these steps carefully:
Open Command Prompt as Administrator
Type these commands one by one and press Enter after each:
net stop wuauserv
net stop bits
net stop cryptsvc
net stop msiserver
Now rename SoftwareDistribution and Catroot2 folders:
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 catroot2.old
Start services again:
net start wuauserv
net start bits
net start cryptsvc
net start msiserver
After this, restart the PC and try upgrading again.
Step 10: Update Drivers Before Upgrading Again
Many stuck-at-99% issues come from outdated drivers. The biggest offenders are:
Graphics drivers (Intel, NVIDIA, AMD)
WiFi drivers
Bluetooth drivers
Storage drivers (Intel RST)
To update drivers safely:
Open Device Manager
Expand categories like Display adapters and Network adapters
Right-click the device
Choose Update driver
For best results, download the latest drivers from your laptop/PC brand website.
If you have a gaming PC, updating the GPU driver from NVIDIA/AMD official tools can make a big difference.
Step 11: Repair Corrupted System Files (SFC and DISM)
System file corruption can stop Windows upgrades at the final stage.
Run these commands:
Open Command Prompt as Admin
Type:
sfc /scannow
Wait for it to finish.
Then run DISM repair:
DISM /Online /Cleanup-Image /RestoreHealth
After that, restart your PC and try the upgrade again.
Step 12: Try the Windows 11 Installation Assistant Instead
Sometimes Windows Update fails but the upgrade works perfectly using the Windows 11 Installation Assistant.
This method is smoother and avoids some download issues. It also keeps your files and apps in most cases.
Steps:
Download Windows 11 Installation Assistant from Microsoft
Run the tool
Accept terms
Continue the upgrade
Make sure you close all apps before starting.
Step 13: Upgrade Using ISO File (Most Stable Method)
If Windows 11 upgrade gets stuck at 99% again and again, upgrading with an ISO file is usually the best choice.
Here’s the method:
Download Windows 11 ISO
Double-click the ISO to mount it
Open the mounted drive
Run setup.exe
Choose Keep personal files and apps
Continue installation
This method often works better because it runs the upgrade in a controlled setup environment.
Step 14: Perform a Clean Boot Before Upgrading
A clean boot helps stop third-party programs from interfering during the upgrade process.
Steps:
Press Windows + R
Type msconfig
Press Enter
Go to Services tab
Tick Hide all Microsoft services
Click Disable all
Go to Startup tab
Open Task Manager
Disable unnecessary startup programs
Restart your PC
Now try upgrading again. After the upgrade is complete, you can enable services back.
Step 15: If Upgrade Still Fails, Check the Logs
If your Windows upgrade keeps getting stuck at 99% repeatedly, the log files will usually reveal the exact reason.
Check these locations:
C:$WINDOWS.~BT\Sources\Panther\setupact.log
C:$WINDOWS.~BT\Sources\Panther\setuperr.log
C:\Windows\Logs\MOSetup\MOSetup.log
Open setupact.log and search for:
Error
Fail
Rollback
0xC1900101
If you find a driver name or app causing trouble, remove it and retry upgrade.
Step 16: Last Option (Only If Nothing Works)
If nothing fixes the stuck upgrade, your last option is a clean install. This takes more time but removes upgrade bugs completely.
Before clean install:
Backup important files
Save browser passwords and keys
Create a bootable USB using Rufus
Install Windows fresh
Most people don’t need this step, but it works when everything else fails.
Final Thoughts
A Windows 11 upgrade stuck at 99% is frustrating, but it is usually fixable. In many cases, Windows is still completing final tasks, so waiting patiently for a while is the smartest first move. If the upgrade truly freezes, disconnecting external devices, restarting safely, and using Startup Repair can bring your system back without data loss.
If the issue happens again after rollback, focus on the most common causes like low disk space, outdated drivers, antivirus conflicts, or corrupted system files. For the best success rate, upgrading using an ISO file or the Windows 11 Installation Assistant often works better than Windows Update.
