This has been a hot topic on X for a while now, but it seems that after installing Windows 11 update KB5062660 or KB5063878, some SSDs are no longer recognized when writing large amounts of data (tens of GB).
In my environment, I installed KB5062660 on Wednesday, July 23, 2025, and KB5063878 on Wednesday, August 13, 2025, and have not encountered any problems even when writing large amounts of data.
Some of you may have already updated, while others may have paused the updates out of fear, but this is a bug that only occurs in certain environments, so if you are not experiencing any problems, we do not think there is any need to force yourself to uninstall it.
If you're concerned, although we don't recommend it, you can uninstall the update and temporarily stop updates.
Microsoft appears to be aware of the issue, but has not officially announced it.
This is just my speculation, but I think the driver may be involved.
In this update (KB5063878) Windows Storage Port Driver Information Disclosure VulnerabilityThis fixes the issue and updates the storport.sys driver.
"storport.sys" is a very important system file in the Windows operating system that manages data transfer to and from storage devices.
This is part of the "Microsoft Storage Port Driver" which is responsible for communication between storage devices, especially hard disk drives (HDDs) and solid state drives (SSDs), and the rest of the system.
Specifically, it is a driver that acts as a hub for high performance storage interfaces such as SATA, NVMe, and RAID controllers.
If there is a problem with "storport.sys",When copying large amounts of data, the process may become extremely slow, freeze midway, or ultimately fail with an error..
This is because "storport.sys" directly manages data transfer between the SSD and the CPU and memory.
If this driver becomes unstable, the data path may become clogged or communication may be interrupted.
In particular, copying operations that involve large amounts of data place a continuous load on this driver, making problems more likely to surface.
"storport.sys" is responsible for initializing the storage controller (the chip on the motherboard to which the SSD is connected) when Windows starts up and "discovering" the connected SSD.
If this driver is not working properly, Windows will not even be able to recognize the existence of the SSD.
As a result, the following may occur:
- The drive suddenly disappears during use.
- The SSD on which the OS is installed is not recognized, and an error such as "Boot Device Not Found" is displayed.
- An exclamation mark appears next to the storage controller item.
This is merely speculation, and the underlying cause is unknown, so it is wise to wait for an official announcement from Microsoft.
2025/08/31 Update: Although Microsoft has not publicly announced this, they have stated that they have not been able to confirm the relationship between this issue and the update.
- [Windows 11] Back up your entire OS for free! Completely restore your PC with your own "custom installation media"
- Repairing system files in Win10/Win11 with "System File Checker"
- Check your HDD and SSD for errors regularly in Windows 10/Win11
2025/08/28 Update:
From here, overseas media sites Wccftech We will explain the SSD issue based on reports.
After thorough testing, Phison, a leading manufacturer of SSD controllers, concluded that it had not been able to confirm that the Windows 11 updates KB5063878 and KB5062660 would cause SSD failure.
According to Phison, after the release of the Windows 11 updates "KB5063878" and "KB5062660," there were numerous reports on social media of SSDs becoming bricked, and initially, Phison SSDs were the target.
However, subsequent investigations revealed that similar issues had been reported in SSDs from other manufacturers.
Phison has conducted over 4,500 hours of testing and over 2,200 test cycles on its SSDs that were reported to be "potentially affected," but ultimately found no issues as reported online.
Phison emphasized to Wccftech that proper thermal management is key to preventing isolated issues like this and maintaining SSD performance and lifespan.
My personal opinion
From here on, these are my personal thoughts.
SSDs are more heat resistant than HDDs and are said to have a lower risk of failure due to heat. However, high temperatures can significantly reduce performance and lifespan for both.Proper temperature control is important.
SSD precautions
Although SSDs have a high upper limit of operating temperature,Easily gets hotNVMe M.2 SSDs in particular are very fast and prone to overheating.
When the temperature approaches 70°C,Thermal ThrottlingThis function intentionally reduces performance.
This causes the data transfer speed to slow down dramatically.Continuous high temperatures accelerate the deterioration of the semiconductor cells that store data, shortening their lifespan.
HDD precautions
HDDs are at risk from temperatures lower than SSDs. Generally, caution is needed when temperatures exceed 50°C, and failure rates increase significantly when temperatures exceed 60°C.
HDD failures often occur suddenly, and in many cases, data recovery is difficult.
Room temperature
This summer has been a record-breaking heat wave, and temperatures are prone to becoming too high indoors.
When performing heavy workloads, the heat generated by the CPU and graphics card can create sauna-like conditions inside the PC case.
Normally, the case fan can take in cold air from outside and cool it down,If the room temperature itself is high, the cooling efficiency will decrease significantly.
The ideal air conditioning temperature for maintaining SSD health is said to be 25 to 27 degrees Celsius, but you may also want to consider where you place your PC.
Warm air flows upwards and cool air flows downwards, so we recommend placing your PC at the bottom.
For laptops, blowing air from underneath will help cool them down.
Features built into Windows 11
In Windows 11, there are services that run automatically in the background.
For example, if the Windows Search service is running, it will simultaneously index files as they are unzipped, copied, or deleted, placing a heavy load on the CPU and SSD.
I have been aware of this issue for some time and believe it may be somewhat related to the current SSD issue.
Therefore, I personally recommend disabling the Windows Search service.
Why Windows 11 slows down when extracting, copying, or deleting files
Also, prefetch files, which are used to speed up the startup of Windows and applications, can sometimes actually affect the speed at which Windows and applications start up.
Simply deleting unnecessary Prefetch files can make your PC run more efficiently and may even fix unexplained problems.
Make your PC lighter in minutes! A tool that automatically deletes unnecessary prefetch files
