Here is the full list of all 18 Tech Support: Error Unknown achievements.
Buy a residence away from it all
Successfully complete 20 tickets in a day
Join the revolution against the corporate overlords
Finish a day with 12 tickets completed, under 45 seconds per completion and 5 stars.
Help Jayesh with his sister
Unlock the achievement through the terminal
Finish the game with no upgrades
Rise the corporate ladder to success
Encounter the game's developer
Buy every upgrade
Become a Lead Tech Support Specialist
Complete the game on professional
Help the law take down the culprits
Help your family in their time of need
Do your 8 to 5, no more, no less
Complete over 300 tickets total during the game
Get the 9.5 million dollars
Unlocked through the BIOS