100% Working Tips to Fix 'Not Enough Space for Windows 10 Update' Error

Usually, when you receive an error message which tells ‘Windows needs more space’, it means that your computer doesn’t have enough space to install the latest Windows 10 such as Windows 10 cumulative update, Windows 10 Creators update, Windows 10 Fall Creators update and even the Windows 10 April 2018 update.
What will you do if you are unable to install Windows 10 update on your computer? This page collects some useful fixes for you to follow and you can follow questions listed below and follow to find fixes for ‘not enough space for Windows 10 update’ error on your PC now:

Notice: When the system doesn’t have enough space for Windows 10 update, most users will be asked to free up disk for resolving this issue. Therefore, here we’d like to recommend you backup important data to an external hard drive in advance. Professional Windows backup software will do the job for you.

When your computer fails to install the latest Windows 10 update with not enough space issue, please refer to two major problems listed below and find fixes right here now:

Problem 1: Not enough system reserved partition for Windows 10 update
- Windows 10 couldn’t update system reserved partition

Mostly, Windows 7 only requires 100MB space for the system reserved partition, but Windows 8 and Windows 10 requires at least 350MB for updating and installing new Windows update.

Therefore, if you failed to install the Windows 10 update with a warning message “This PC can’t run Windows 10...we couldn’t update the system reserved’ partition”, mostly, it is caused by low system reserved partition space. 
The straightforward solution to this cause is to extend the system reserved partition. So how to fix this issue? 
Troubleshooting: extend system reserved partition for Windows update

Problem 2: How to fix not enough space for Windows 10 update issue? 
- Windows needs more space

Another problem for Windows 10 update is not enough (disk) space for Windows 10 update. It’s mostly caused by low disk space especially not low disk space on C drive. 
To fix this issue, we’ve gathered four methods, and you may apply any one of them to resolve this problem now:

Fix 1. Check, extend and increase system C drive

If the system (C:) drive is with low disk issue, it won’t be able to install and save new Windows 10 update files on your PC. 
So if your computer is running out of space for installing the latest Windows 10 update, we’d like to recommend you check out whether your system C drive has enough free space for installing the new update.
If not, please refer to extend system partition in Windows 10 to increase your C drive space. 

Fix 2. Clear and free up disk space for Windows update

Another way for solving 'not enough disk space’ issue in Windows 10 update is to clear and free up disk space.
There are many ways of doing this job. Mostly, you can use the Disk Cleanup command to free up disk space on your PC.
Or, you can also refer to a third-party disk cleaning tool for help. Here you can refer to powerful partition manager software - EaseUS Partition Master for help. 

For a more detail tutorial, please refer to how to free up disk space for assistance. 

Fix 3. Install Windows 10 update using an external hard drive

If your computer disk doesn’t have enough space for installing the latest Windows 10 update and you don’t want to purchase a new bigger hard drive, you can use an external hard drive as a temporary drive to add space to your computer and complete the Windows update process.
Here are the detailed steps to fix not enough space for Windows 10 update issue by using an external hard drive:

Step 1. Go to "Settings", click on "Update & security" > "Windows Update" > "Check for Updates".
Step 2. Windows will pop up a window and tell you that "Windows needs more space".
Step 3. You can click "Free up space" option first to see if this can help.
You can see what’s taking the most space on C drive and delete not essential files.

After this, return and select the Fresh icon next to the Free up space button, a green check mark will show up if the C drive has enough space.
You can click Continue to install the update.

Step 4. If this doesn’t help, connected an empty external hard drive to your PC and repeat Step 1, click "I want to use external storage instead" when the ‘Windows needs more space’ window pops up. 

Note: Please format the external storage such as external hard drive first in case Windows update fail again. 

Step 5. If the external hard drive fails to show up, press the Fresh icon and a green check mark will appear next to the storage drive icon.

Step 6. Click Continue to install the latest Windows 10 update on your PC.

And all you need is to follow the onscreen instructions to complete the Windows 10 update process.

Fix 4. Migrate OS to a bigger HDD/SSD for Windows update

If you think Method 1, 2 and Method 3 are all too complex for fixing not enough space for Windows update issue on your computer, the last effective way you can try is to migrate your current OS to a newer and bigger hard drive or SSD for help.

Although this would cost you quite a bunch of money for purchasing a new HDD/SSD, you’ll get a faster and more efficient computer with new Windows system.
If you choose the last method, please refer to migrate Windows Operating System to SSD/HDD for a detailed tutorial with EaseUS Partition Master. 

Note: After migrating the OS to a new hard drive, please do remember to change the boot order in BIOS. Set computer to boot up from the new hard drive.

And then you can continue updating and installing the latest Windows 10 update on your computer now.