We all have those moments when nothing seems to work the way it should. When you have one of those moments, don’t panic. Follow some basic steps.
If the keyboard, mouse, printer, etc. isn’t responding — check cables (both ends!). If it has a power switch, turn it off and then back on. If it has batteries, do they have enough charge?
If a program isn’t behaving properly, quit it and then restart it. If it still misbehaves, try logging into a new, clean identity and try it again. If it work then, it’s probably a corrupt preference file in your home library. If it still doesn’t work, try restarting the computer. If all else fails and you haven’t made any changes to the operating system, try uninstalling and reinstalling. Don’t just trash the application. Use something like AppZapper to delete it. AppZapper will usually find all of those pesky hidden additional files that you miss when just trashing. Additionally, you can use AppZapper to trash only those corrupt preference files. Just uncheck the app files before you hit the zap button.
Internet seem to be running slow? It could be a problem with your service provider, but it’s more likely that your modem and router need to be rebooted. I know mine benefit from an occasional reboot. If you are going to do this, turn off modem, router and computer. Give it a good 30 seconds, then turn on the modem. Give it time to run all of its internal checks. Once all lights are green, turn on the router. Again, give it a chance to run those internal diagnostics, then turn on the computer. You should be back up to speed. Oh, and if you have a wireless printer on your network, you may have to turn it off and then back on to make it reconnect.
If you have an iPhone or iPad (or a Kindle or other ereader), it can also benefit from an occasional restart. Most of them just stay in sleep mode when not in use. With an Apple device, hold down the power button for a few seconds until the “slide to power off” dialog comes up. Follow the prompt, and after it completely shuts down, power it back up. Clears up a bunch of problems. Individual iApps that quit unexpectedly may have to be deleted and redownloaded.
Remember, don’t panic. It’s probably something simple.