If the PC has already been rebooted after enabling mining for this machine then:
Usually, if the PCs has successfully downloaded the ggCrypto Modules it should wait for ~2 minutes to start mining to make sure that no user is about to login
Sometimes Modules takes a while to be downloaded 5~10 minutes (for very slow connections)
If it has been more than 5~10 minutes and the miner still hasn't started please do the following:
Admin Mode the PC
If you have a 3rd party anti virus, please check your antivirus add check if it quarantined the files related to the miner
Look for quarantined items with "Phoenix", restore the file and add exception.
If you don't have a 3rd party anti-virus
On Windows, go to Settings > Windows Update and Security > Windows Security > Virus & threat protection
On Virus & threat protection go to "Current threats" and look for threats that has "Phoenix" on it and select "Allow on device", then click "Start Actions" button, and reboot the PC.
If the issue still persist, please contact ggSupport via Intercom chat.