[Trisquel-users] How to Enable PAE?

[susanbryce11]

Hello, on a number of old laptops I get the following problem when I try to  
install Trisquel....

The ISO image will fail to boot ("This kernel requires the following features  
not present on the CPU: pae.") If a few lines above this text there is a  
warning "WARNING: PAE disabled.

Can anyone please suggest a safe way to fix this?

thankyou