Like previous versions of Windows, Windows 10 also uses disk partitioning system where OS drive (usually C drive) generally stores all Windows system files and program installation files. The users who have smaller Hard disk drives or the ones who play heavy games know that how hard it is to manage in smaller disk space. Eventually the space in C drive get’s filled up and you start getting pop-ups for clearing some space.
This storage issue with OS drive (C drive) has significantly worsen after Microsoft started pushing Windows updates that are cached and stored in the C drive for recovery purposes. You can still use some cleanup tools but that space will be filled again on next Windows update. In such scenarios, users don’t have many options but to increase the OS drive (C Drive) space. The process of increasing space in C drive is not very straightforward and may get you confused. That’s why we are here with an in-depth tutorial on how to extend C Drive Space on Windows 10.
We will be using two utilities to extend C drive space on Windows 10 – native Windows tool – Disk Management & third party tool – AOMEI Partition Assistant. Let’s start with Windows Disk Management tool.
Extend C Drive Space on Windows 10 using Disk Management
First, we will be using the native Windows tool — Disk Management — to increase the space of C Drive. This tool comes built in with Windows 10 already and used for managing disks on Windows 10. The process of extending C drive is quite simple and chances of data loss are very low, we still recommend that you take backup of your important files and folders. Before we move ahead, let’s have a brief overview of how we are going to extend the C Drive storage space.
Please note: You can only extend the volume of C Drive if the nearest drive (which is D) is empty and unallocated. You can’t extend the C Drive storage from E or F or the next drive. So, what you can do is, either move your files from D drive to other drives like E or F and so on and then extend C drive. In case, you don’t have available space on any of the drives then back up D Drive files to an external hard disk. This way you can empty D drive and merge it with C drive. Follow these steps:
Right-click on the Windows Start Menu and open “Disk Management”. Alternatively you can go to RUN, type ‘diskmgmt.msc‘ and press Enter.
We are assuming that you already have taken back up of all your files from D Drive. Now, right-click on D Drive in Disk Management and click on “Delete Volume”. It will delete the partition and make it an unallocated partition.
Next, right-click on the C drive partition and select “Extend Volume”.
Please Note: If the “Extend Volume” option is grayed out then you will have to use a third-party tool. You can find all the instructions in the next section. However, before moving on, create a new volume using unallocated space. You can use this partition in the next section.
A pop-up window will open up. Keep clicking on “Next” and select options for extending the C drive to occupy full or partial space of D drive and finally click on “Finish”.
Finally, your C Drive will be merged with D drive and storage space will be increased instantly. So this is how you can extend C drive space on Windows 10. You can also shrink space in C drive if you have excess space.
How to Extend C Drive Space with AOMEI Partition Assistant ?
In previous section, we merged the whole D Drive with C Drive. However, if you want to add just few GBs of space (say 10 or 20 GB) or whatever part of storage from D or any other drives then you can use AOMEI Partition Assistant. It’s a third-party partition manager that comes with a broad range of features. Download link is provided at the end of the post. Keep in mind, even this way, you need to back up all your files just to be on the safe side of things.
Also, if the native method failed to extend C drive, then we would recommend you go through this method. Specially when the “Extend Volume” option for C Drive is grayed out in Disk Management, you can use AOMEI Partition Assistant.
Right-click on any drive that has available storage and select “Resize/Move Partition”. In case, you have tried and failed using the above method, please select the new partition that you created earlier through new simple volume wizard.
Next, using the slider, choose how much space you want to keep in the existing drive and click on the OK button. In this tutorial, we have kept approximately 800GB from 821GB which means we are taking out 21GB from the existing drive. We are going to merge this 21GB with C Drive. You can choose your own storage space depending upon your requirements.
Next, right-click on the newly-formed drive (which is actually un-allocated space) having a storage of 21GB (in my case) and select Merge Partitions.
Here, select C: drive and the unallocated drive from the list and click on the OK button.
Finally, click on the Apply button at the top-left corner and then click on the Proceed button to apply the changes we made. This process may take up to 20-30 minutes to complete the whole process. Your computer might restart several times during the process. In case you see an error, don’t panic, simply restarting your computer will get you back to your PC.
After above process completes, the C Drive will be extended without any data loss. So that is how you can increase C Drive space on Windows 10 using the AOMEI Partition Assistant.
Increase C Drive Space in Two Easy Ways
Above tutorial explained how you can expand the storage of C Drive using the two methods mentioned above. While the Windows native method is simple and straightforward, it may not work due to “grayed out Extend option”. However, in such a case, you can use AOMEI Partition Assistant which works quite well. Hope you found the article helpful. In case you are facing problems, let us know in the comment section down below. You can check how to speed up Windows 10 if your Windows 10 is getting slow over time.
Download AOMET Partition Assistant
You can download latest version of AOMEI Partition Assistant from the link below.