Thanks for posting to the Community, @thinkfirstactsec.
To generate a one time check, you can change the pay method column from direct deposit to paper check and modify the salary/hours acquired by the employee.
Let me show you how:
- Go to Workers and then select Employees.
- Click Run payroll.
- On the employee column, check the box for the employees you wanted to pay one time check.
- Change the pay method by clicking the Direct deposit to change it to Paper check and the salary/hours acquired by the employee.

- Click Preview payroll.
- Hit Submit payroll.
- Select Finish payroll.
Then you can manually write employee's net pay on a check or order check stock from Intuit preprinted with your bank and company information.
For more details in issuing a one time check, you can refer to these articles:
What exact error message you got? This way, I can narrow down the issue and get you a more spot-on fix.
Please feel free to leave a message through this post if you need more help. I'll keep my notifications open. Have a good day!