Steam is the most popular social gaming platform for PCs today. As entertaining it is to have access to this platform for buying and playing games, it quickly gets frustrating when you can’t run your favorite one. Steam Disk Write Error is what gamers commonly encounter when downloading, updating, or installing a game.
There is no single most effective solution to this error as it happens for several reasons. It can be anything from outdated software to overaged hardware.
Causes Of Steam Disk Write Error
It is hard to verify what might be causing a Steam Disk Write Error as common as it is. Since Steam only writes data while updating & installing a game, that’s the only time you encounter this error. However, we’ve streamlined the following causes for a disk write error.
Write-Protected Drives

Write-protected drives are read-only drives where you cannot change data storage. If your Steam installation’s source location is in a write-protected drive, it is likely for it to be the cause of a disk write error.
Selecting the directory for your Steam installations is always crucial to your gaming experience. Suppose you fail to consider write protection and storage concerns for Steam Library. In that case, you’re bound to run into a few problems now and again.
Blocking by Anti-Virus or Firewall

Another basic cause for a Steam disk write error is the application being blocked by a firewall or anti-virus. It happens because many modern developers prefer using copy-protection technology for their games. And such privacy for an internet-integrated app may appear malicious or infective to your anti-virus.
Moreover, the default firewall permissions are pretty strict, and for a good reason. However, they, too, may interfere and prevent Steam from communicating with its servers. And when that happens, you get a Steam Disk Write Error pop-up on your screen.
Defective or Bad Sector of the Hard Drive

Disk Write Errors are more common in HDDs than in SSDs. It is because of the mechanical tape that gets fragmented and defective quickly. But, as common as it is, it is usually fixed with the default Windows defrag.
However, it portrays a very different concern in SSDs. Because by the time you get a disk write error on an SSD, you’ve probably lost your hardware’s integrity anyway.
How to Fix Steam Disk Write Error?
Knowing what causes the problem is one side of the solution. If you know from the above text what might be causing the disk write error on Steam, you can toggle to the right heading and find a fix. Otherwise, going through the following fixes numerically will fix your disk write issue.
Restart

Have you tried turning it off and on again?
Yes, you’ve heard that one before! And yes, again, it applies to Steam as much as it does to anything. Try switching your Steam client off and give it a few seconds until you relaunch it. See if it fixes the error. If not, try restarting your computer.
Run as Administrator

When you run a program or an application as an administrator, it will likely bypass basic permissions and firewalls. And for clients like Steam, you usually require an extra set of permission to communicate to servers.
The easy way is to right-click on the Steam launcher and click “Run as Admin.” But a more permanent solution is to go to the properties of the launcher icon, select the “Security” tab, and choose the Admin entry.
Remove Write Protection from the Drive

Suppose your Steam directory is either in a read-only mode or in a write-protected drive. In that case, it will not allow data editions. And so, you get to see the disk write error on your screen.
You can right-click the launcher and run it as administrator if the directory is not in a write-protected drive. Or, you can launch the launcher’s properties and uncheck the “Read-only” box.
For a write-protected drive, you’ll have to remove write restrictions from the drive before you can correct your Steam launcher settings and properties.
Check and Repair Bad Sectors of the Hard Drive

Bad sectors are compromised traces of data. Sometimes, they fragment your hard drive and can easily be eliminated. While others, you may need a hardware replacement depending on the errors and age of your HDD.
To check and repair bad sectors of the hard drive, run a complete error check for the drive that Steam is installed in. If you encounter a few dozen errors, upgrade your hard drive!
If there are too many errors on your hard drive from the error-check, you may want to completely wipe your hard drive before you replace it. It’s not a sure way but sometimes, it does save you money and fix the error.
Delete Corrupted Files

When your download or update doesn’t go accordingly and encounters a crash, it may create a corrupt file. These corrupt files are also a reason for disk write errors and can keep bugging you until you delete the corrupted file.
Navigate to the “steamapps” folder and open the “Common” directory. If you see your game file or any other file that is 0KB, you’ve probably found the corrupt file. Delete the file and restart the installation.
Remove Download Cache

A steam download cache can build up significantly over time. And if you’re short on storage as well, the cached data may begin to corrupt and bug your client. Clearing the Steam cache will force the client to fetch new data from the servers without corrupt files.
Clearing the download cache is fairly simple. Open the Steam client settings, go to downloads, and click on the “Clear Download Cache” icon.
Update Windows and Drivers

An outdated Windows or driver may prevent some permissions to your Steam client. New games and releases rely on updated settings and features, and if they are missing, you may encounter the Steam disk write error.
You check for a Windows update by typing “Windows Update” in the start menu and opening the settings option. For a driver, you’ll have to open “Device Manager” from “Computer Management” and see if you’ve got any yellow question marks in the list.
Choosing the right version of Windows 10 Home or Pro may too show improvement for future reference. The extra features of the Pro edition may be enough for Steam to play around in.
Disable Antivirus and Firewall

We’ve already covered why and how your Windows Firewall or Antivirus may prevent Steam from downloading and installing data. For a quick check, turn the Windows Firewall off and see if it works. If not, turn off the Antivirus as well. It might work, then.
If turning off one or both of the security options solves your problem, you may want to grant Steam an exception. Go to Firewall settings and grant Steam access, then do the same for Antivirus.
Disabling windows firewall and Antivirus permanently is a common computer security mistake to avoid. You must immediately turn them back on once you’ve fixed your Steam error.
Reinstall Steam

Reinstalling the client-server will eliminate all corrupt files, data, and bugs. And you can do so while keeping all your games and saved missions.
However, it is important to note that you must Reinstall and not delete the Steam app. Deleting it will eliminate all the games and saved data you have on the client. A quick reinstall, on the contrary, will fix your Steam disk write error.
Conclusion
Steam disk write error is a rather common problem PC gamers come across. Although it is a pain when you can’t eliminate it, it is not something to fret about a lot. We hope you’ve found a fix for your problem from the guide above. If not, you can Contact Steam for help, as they’re always willing to improve their interface.