To open System Information directly, press and hold the Option key and choose Apple menu > System Information. You can also use Spotlight to find System Information, or open it from the Utilities folder of your Applications folder.
It should open up a window that looks like this,
Click the button that says "System Report"
It will open up a window that looks like this:
Select File -> Save
It will open up a File Dialog asking you where you want to save that file.
Specify where you want to save it, and remember that folder so you can go back and find the file you saved.
You will see a loading bar until it finishes saving the file
Find the file that you saved and send it as an attachment to tech support