Genshin Impact Error checking game files?

Today I tried to install Genshin Impact on my computer three times, I have Windows 8.1 and it is an older laptop, but it still works fine and I can still play on it. (Well, you can no longer buy the laptop because it is very old, but I currently have no money to live with and a new PC or laptop is not an option.)

I install the game at 5mb / s and when it finishes I get this error message, on the website for the most common questions you can find nothing more than very useless information

That is the question

Q8: When downloading, I get the message: "There was an error checking the game files. Please try again to resolve the problem."

That is the answer

A8: Please click "Try Again". If you still have problems, try restarting the game or downloading it again.

Since I installed it 3 times and it still contains this error and I haven't found it on other platforms, I ask you if you know a solution.

Thanks for taking the time and reading my question

Have you tried Run as Administrator before?

No not yet, because I thought it didn't make any sense because it ends at the Installation's Launcher anyway, but I'll try the installation again today.

Did you delete everything before reinstalling? For example, there are files in AppData that have to be removed.

Take CCleaner and clean up your registry and restart your computer before you install.

Thanks for the advice. Yes, I will try this out and report what happens.