Just try the solutions mentioned in thisMiniToolpost to help you out.
The result might be not satisfactory: you seeThis PC cant run Windows 11.
You could also see this warning pop-up during the Windows 11 setup process.

The error alert interface always shows you the reasons for This PC cant run Windows 11.
Here are the collections:
You know the reasons.
So, the issue might be solved.

In this post, we collect some useful and effective solutions.
You could jump to the corresponding part to view the solution according to the case you are facing.
In a situation like this, you might need to enable TPM 2.0 on your machine.

According to this glitch notice, Windows 11 needs 64GB or larger space on the system disk.
How to Check the Free Space on C Drive?
Microsoft might make some changes in the future.

Or, you could purchase a new computer that supports running Windows 11.
The Windows 11 update process might last for hours and your box will restart several times.
You should wait patiently until the whole process ends.

If you have backed up your box in advance, you could restore your data from the backup file.
However, if there are no available backups, what should you do to get your lost data back?
In a situation like this, you could use professionaldata recovery softwareto have a try.

MiniTool Power Data Recovery is a good choice.
This tool is specially designed to recover all kinds of data from different data storage devices.
You could use it on Windows 11/10/8/7.

It has a free edition, which allows you to recover up to 1GB of data.
If it is the first time for you to use it, you could try thisfree file recovery toolfirst.
If the result is positive, you could then use a full edition to recover more files.

- pop swing open the software.
This software shows you all partitions it could detect under Logical Drives.
Hover over the drive you want to recover data from and click theScanbutton to start scanning that drive.

If there are more than 10 partitions, it only shows you the first 10.
You could open each partition to find your needed files.
This software supportspreviewing up to 70 types of files.

In the free edition, the previewer is not included.
Then, you could preview files for confirmation.
Select your needed files.
Click theSavebutton (on the bottom-right corner).
Select a location to preserve your selected files.
To prevent your lost data from being overwritten, the destination location should not be the original drive.
You could directly use the recovered files.
Bottom Line
Bothered by this PC cant run Windows 11?
This article shows you different situations and solutions.
You could choose a corresponding solution according to the issue notification you see.
Hope these methods are helpful to you.