1. Click on the Start Menu
2. Click Run
3. Type CMD in the Open textbox and click OK
4. In the command window type:
net user accountname /times:M-F,8am-8pm; Sa,8am-5pm;Su,8am-1pm
Replace accountname with the name of the account you wish to limit. The time command is a bit tricky, but the above example is easy to replace with the appropriate values. Here’s microsoft’s further information regarding the format of the time command:
Specifies the times that users are allowed to use the computer. Time is limited to 1-hour increments. For the day values, you can spell out or use abbreviations (that is, M,T,W,Th,F,Sa,Su). You can use 12-hour or 24-hour notation for hours. If you use 12-hour notation, use AM and PM, or A.M. and P.M. The value all means a user can always log on. A null value (blank) means a user can never log on. Separate day and time with commas, and units of day and time with semicolons (for example, M,4AM-5PM;T,1PM-3PM). Do not use spaces when designating times.