Last updated on May 6, 2024
When the System C drive is almost full and has no space, you will find the C drive capacity meter displays in red, as shown in the following picture. When the C drive or D drive runs out of disk space, you receive an error message indicating low disk space.
Low disk space error
When System C drive is full and shows red stripes, there's no room for saving new files or installing Windows updates and apps. You may also experience slow, laggy, or even crashing Windows 10.
Read more: How to Fix Yellow Triangle Warning on C Drive
How to get rid of the low disk space red bar on C drive and free up C drive space to improve computer performance? On this page, you will learn how to disable the low disk space red bar on Windows 10/8/7 with several easy and effective solutions.
Next, we will explain the most practical ways to fix the C drive red bar and low disk space issue. Read on for details.
As you know, when you see the red bar on C drive in Windows 10, it indicates that there is not enough space available. So the first thing you need to do is to extend C drive to fix the low disk space error.
The world-renowned disk management tool, AOMEI Partition Assistant Professional, offers the "Smart Space Allocation" option to help you expand the C drive with one click. No data will be lost, and there is no need to delete partitions.
If there's unallocated space on the disk, the partition manager will extend C: into the unallocated space. If there's no unallocated space, the software will automatically resize another partition to give space to C:.
Now, download and run Partition Master, then follow the simple steps below to add space to C drive with just a few clicks.
Step 1: Click "Optimize" to expand the C drive.
When the C drive is low on space, hover over it and you'll see a “Low disk space” warning on the Partition Master tool. Click “Resize/Move” to extend it.
Click "OK" to automatically expand C:.
Click “OK” and Partition Master will automatically allocate space from Drive D to Drive C, solving the low disk space problem.
Optional: You can also click “Customize” to manually expand the C drive.
Select “Resize Manually”, check the C drive, drag the allocation point to the right to increase the space of C drive, and click “OK” to finish.
Step 3: Confirm that you have resolved the low-C-drive-space issue
Click the “Run Tasks” button in the upper-right corner, and then click “Apply” to begin all pending operations.
Junk files from Windows or apps can take up a lot of space on your C drive. Run a system clean-up with a free tool to delete junk files and save disk space. This will free up more space on your C drive, getting rid of the red bar.
Step 1. Download and install the Partition Master Suite.
Step 2: Click on PC Cleaner and install the tool CleanGenius. Then click “Clean” and “Scan” to start cleaning your system and restore your computer to its former glory.
Step 3: The software will scan your computer for idle data files that are taking up a lot of disk space. You can choose to get rid of unnecessary large files, system junk files, and invalid Windows entries, then click on “Clean” to start the cleaning process.
4. After the scan is finished, click “Finish” to clean up system junk files.
Emptying the Recycle Bin is a useful way to free up space on the C drive and fix the red bar issue in Windows 10. Windows keeps deleted files in the Recycle Bin for 30 days or more.
If you never empty the Recycle Bin, the deleted files will take up some space on your system C drive, causing it to fill up. That's why we recommend regularly emptying the Recycle Bin to free up space.
Step 1: Right-click the Recycle Bin icon on your desktop.
Step 2: Select “Empty Trash” to get rid of unnecessary files.
Click "Empty Recycle Bin" to free up space on C drive.
Many programs are set to install on the C drive by default, causing it to fill up fast and turn red. You can easily and safely transfer programs from the C drive to the D drive using a PC transfer tool like Todo PCTrans.
Note: Moving the installer manually to another drive may prevent the program from running due to missing boot files.
If the system disk itself has insufficient capacity, freeing up space on Disk C won't help much, and you frequently receive red warnings about it being full, you can consider upgrading your system disk to a larger HDD or SSD.
How can you upgrade the system disk without reinstalling Windows or applications? You can use the "Migrate OS" feature in "Partition Assistant." This software will automatically clone the C drive and boot partition to the new hard disk, ensuring no boot issues after migration.
Steps to migrate the operating system to an HDD/SSD:
“Restart Now” saves the changes and restarts immediately, while “Finish” saves the changes but requires a manual restart later.
Note: If there is not enough unallocated space on the target disk, the OS migration operation will delete and remove existing partitions and data on the target disk. Back up any important data to an external hard drive beforehand if necessary.
This tutorial covers five effective ways to help you fix the Windows 10 C drive red bar issue. You can tackle the problem from three aspects:
Should you encounter any issues while resolving the C drive red bar problem, feel free to reach out to our Technical Support team for assistance via live chat or email at techsupport@tools.com.
Here are some popular topics related to the Windows 10 C drive red bar issue. Please check out the brief answers to these questions.
If your C drive is shown in red in File Explorer, it means that there's not much free space left, and you might not be able to install new Windows updates, programs, or files. In this case, you'll need to try some methods to free up space on the C drive or expand the C drive.
The issue of the C drive turning red can be resolved in the following ways:
If "This PC" is on your desktop, double-click it to open. You should then see the C drive listed, which you can click to access. If "This PC" isn't on your desktop, type "This PC" or "File Explorer" into the search bar, then click the C drive from the results. Alternatively, type "c:" into the search bar and press ↵ Enter to directly access the C drive.
Just like solving the red C drive issue, when your D drive shows red stripes and is almost full, you can free up space on D drive by deleting temporary files, junk files, and large files.
If cleaning up Disk D still cannot solve the problem, you can use Partition Master to extend it. You can simply allocate more space to Disk D by dragging the start or end point of the partition through the “Resize/Move Partition” function in the partition manager.