How to Clear the PRAM

Symptoms: 

Boot issues, such as slow to start or halted startup.

Causes:  
PRAM is non-volatile memory used by the Apple computers to store configuration information. However, certain changes might remain stagnant in residual memory which can lead to bizarre behavior(s).

Solution: 
Power off your computer. Then power the device on while simultaneously holding down the [command]+[option]+[P]+[R] keys. You should hear the Apple chime before the computer reboots. Continue holding the keys down until you hear the second Apple chime to clear the PRAM.

Mac won’t shut down

So, you’ve tried to shut down your Mac but nothing is happening. The first thing you should do is give it time, as OS X has to sort through all its open files and close all programs before it can safely shut down. If, after around five minutes, you’re still staring at the same screen, something hasn’t gone to plan and its time to take action. Take a look at the Dock, and make sure there are no bouncing app alerts or open apps that could interrupt the shut down process. It may be a word processing app that’s stopping the shut down before you save your documents.

It’s also worth checking to see if there are any frozen applications open, as frozen apps can stop a Mac from shutting down, and manually closing them may speed up the shut down process. Identify any open or frozen apps in the Dock and either Quit or Force Quit them before trying to shut your computer down again.

As a last resort, you can force your Mac to shut down, but doing so may cause issues with file corruption, as mentioned earlier. To manually shut your Mac down, press and hold the power button on the back of the Mac until your screen goes black and the system shuts down. It’s worth noting that this should be done once in a blue moon, and if you find yourself doing this regularly, it may be worth reinstalling OS X

How to make your Mac connect to the most reliable Wifi Network

Do you have a couple of wifi options but your mac system keeps connecting to a slow network from the list of wifi.

Simply identify the 5GHz and tell your Mac to join the 5GHz network in preference rather than the 2.4GHz network

To do this, go to System Preferences > Network > Wi-Fi > Advanced. From the Advanced Wi-Fi Settings menu, simply identify your 5GHz network and drag it to the top of the list.

You’ve now told your Mac to join the 5GHz network whenever possible, leaving more room on the 2.4GHz frequency for devices that need it, whilst at the same time providing you with a more reliable and speedy Wi-Fi connection.

Constant “Security” Warnings While Browsing

While this may be one of the most annoying problems, it’s also incredibly easy to fix. Check that your computer’s clock shows the correct time and date. If it doesn’t, right-click on the clock and select “Change date and time settings” to correct it manually.

File opens with wrong program

If a particular type of file no longer opens in the correct program, right-click the file in question and then simply select Open with > Choose Program.

Select your chosen program from the list (click Browse if it's missing), and make sure "Always use the selected program..." is ticked. Then click OK; this will save your preference whenever you open files of that type.

Create a repair disc

If your PC didn't come with a Windows installation disc, click Start, type "backup" and click Backup and Restore.

Select "Create a system repair disc" and put a blank CD or DVD in your writable drive to create a bootable disc with the "Repair your computer" options on it.

No Sound/Audio in Windows

 Before running the Microsoft Fix It Center tool (see tip three), open the "Sound" or "Sounds and Audio Devices" Control Panel.

Select the Playback or Audio tab, and verify the device is set to be the default; if not, select it from the list to fix the problem.