Minecraft – The day to night cycle stopped working! Help!

Using command blocks and some redstone, this can be achieved.

First of all, you need to set /gamerule doDaylightCycle to false, to stop the natural daylight cycle. From here, we are going to use command blocks (/give <username> command_block), some redstone, and the command /time add <number> to control the daylight cycle.

Here is a very simple, and pretty easy to tune setup:

The command on the command block is /time add <number>, tuned however you would like (1 item in the clock with an increment of 5 results in a 28 minute day). There is no hidden redstone, and both pistons are sticky. The hoppers feed into each other, and you choose the number of items put in (more items means slower day/night cycle).

The formula for calculating the length of daytime is 140 * (items / number) minutes of daytime (double that for the length of a whole day).

You're also going to want to use the command /gamerule commandBlockOutput false if you don't want periodic chat updates saying Added 1 to time.

You're also going to want to put this in your spawn chunk if you intend for it to work no matter where you are in the world (determine your spawn chunk by breaking your bed and killing yourself).

as he has pointed out he is using windows 8 so as most of us know sometimes its not as easy to change the settings

Open Windows Firewall by swiping in from the right edge of the screen, tapping Search (or if you're using a mouse, pointing to the upper-right corner of the screen, moving the mouse pointer down, and then clicking Search), entering firewall in the search box, and then tapping or clicking Windows Firewall.

Tap or click Turn Windows Firewall on or off . Administrator permission required You might be asked for an admin password or to confirm your choice.

Do one of the following:

Tap or click Turn on Windows Firewall under each type of network that you want to help protect, and then tap or click OK.

Tap or click Turn off Windows Firewall (not recommended) under each network type that you want to stop trying to protect, and then tap or click OK.

Once you have done that see if it works, if it works then reenable your firewall and select the advanced settings and allow access to the application of choice. you can leave your firewall off if you really want but please remember this leaves you open to risks.

If it doesn't work then it will be something to do with your router and possibly the change of computer and it would be worth re setting up the port forwards.

Hope this has helped.