The CS50 Appliance 19 Manual says:
How to Change Time Zone
If you don’t live in Cambridge, Massachusetts, USA, you may want to change the appliance’s timezone. Select Menu > Administration > Date & Time. Click the Time Zone tab, select the nearest city in your time zone, then click OK, leaving System clock uses UTC checked.
But when I go to Menu > Administration, I can't find Date & Time. Rather, there's this System-Config-Date. It does not do anything when I click it.
Well I didn't find a UI way, but there's a command line way if you're willing. Note: This is using version 19 of the CS50 Appliance.
1) Open up a Terminal session.
2) Type cd /usr/share/zoneinfo and hit Enter.
3) Type ls and hit Enter to see:
4) View the various options available to you. Note that the blue text (like Africa and America) are folders with more options. For instance, in America is:
5) When you've found a file corresponding to your time zone (I'm using New_York in the America folder as an example) type sudo ln -sf New_York /etc/localtime and hit Enter to set your local time.
6) Type date and hit Enter to verify it worked.
Let me know if you need more clarification or specific instructions to what time zone you're in.
1) Click the CS50 Menu, select Settings Manager.
2) Select Time and Date under the System heading.
3) Click the Unlock button and enter in the system password (crimson by default).
4) Select Time zone.
4b) Note: I tried selecting "Keep synchronized with Internet servers" for the Configuration, and while it gave me an error when trying to install NTP support, it still adjusted the clock to the correct time, so might be worth a shot.
5) Adjust the time if needed.
6) Hit close.
Sudo - A command you can add to the beginning of a command to tell the terminal to execute it with admin rights. In most cases, it'll ask you for a password afterwards (I honestly don't know why it doesn't here). ln - stands for "link", meaning to link one file to another. Think of it like a Windows shortcut. This is preferable to just copying the file over because if the appliance updates its timezone definitions, your local one will update as well.