Substance 3D Painter can be unstable if the paging file ( swap memory/ virtual memory) is set with a value too low .
It is advised to let the Operating System handling these settings (which is normally the case by default). Substance 3D Painter requires a minimum of 16GB of virtual memory in order to work properly.

How to change the virtual memory size on Windows ?

Access the virtual memory settings with the following steps

1. Right-click on the Computer/This PC icon and choose Properties
2. Select "Advanced System Settings
3. Click on the Settings button of the Performance section
4. Click on the Advanced tab
5. Click on Change in the Virtual Memory section

Now it is possible to either:

• Enable the checkbox Automatically manage paging file size for all drives

or

• Select the hard drive where you want to change the virtual memory size and choose System managed size and click on the Set button.

Automatic:

Manual: