Ok, so initially, Paint Tool Sai doesn’t work on Windows 10 for some people. So here’s how you fix that. 

First of all, go to the folder where your program is installed. This is either in your C: drive in the “Program Files” folder, or, it’s running from a separate location, either way, you can use the Windows Search option with “Sai” to find it if you’re having difficulty.

Open the folder and right click on the Sai icon that’s marked “Application”. Not the green square one, the actual application with the Sai logo. 

Click “Properties” and then “Compatibility” 

And click “Run Compatibility Troubleshooter”. 

Allow the program to detect problems. It shouldn’t take too long, so be patient! 

Click “Try recommended settings”

This pop up will tell you what mode you will need to run it in, luckily, Windows will set it for you and allow you to test it. So click the test!

Cool! It works! 

If everything is fine (and it should be); click to close the troubleshooter and allow it to run one final check. If not, click explore additional options to open Windows Help, or, go back to Properties as seen in images 3 and 4, and test the different compatibility modes manually. 

You may need to back into the Properties box anyway to turn on the Compatibility Mode as this may not be checked, however, the compatibility you need should already be selected still.

You could also need to check “Run this program as administrator” too.
 Make sure you click “Apply” afterwards.

And that’s it! Enjoy drawing with Windows 10! 
Don’t forget you might need to set up your tablet settings again too and change your Maximum Canvas size in Others > Options > Workspace Usage

I should also say that this method would work with other programs too, including Manga Studio and Clip Studio Paint.

I hope this helped! 
Please reblog this to help others! 

Neonlink~