"Too many tracks recording" prompt when recording only 4 tra

I am recording with Cubase LE8 Ai with a USB interface from my Allen & Heath ZEDi-10 mixer. I have signal from the 4 inputs but as I record I get the “Too Many Tracks Recording” prompt after only a few bars. Sometimes it records longer. I am using a laptop with a Windows 10 home up-grade. A 7200 rpm HDD, 4 gigs of ram and an Intel® Core™ Duo CPU. T9600@2.80GHz. X64 based processor on an HP Workstation. I don’t know the vintage of this Workstation since I bought it on-line with W10 already installed on a clean HDD. Perhaps I need to optimize the laptop for audio recording in Windows 10 Home. All suggestions and help will be GREATLY appreciated.
Ed