When some of your apps start playing up, try cleaning caches.

The Shift key might get you out of troubles, quickly. Going back to history, seasoned users who used System 7 might even remember that they could bypass loading extensions during start.

... it doesn't always need to be a hardware fault, or dust blocking vents. It could just be a software issue which makes your CPU running warm, so the system needs to cool it down. Go to Applications > Utilities ( a shortcut from Finder is cmd-shift-U) and find Activity Viewer. Then set the menu View > All Processes. Then keep watching CPU pane with processes sorted from the highest %CPU to the lowest. The “rogue” processes would appear on the top. Typically, the CPU load of Office programs and usual stuff such as mail is quite low. Safari can be diverse - some...

Please follow these instructions before you come to our service centre as it may speed up the repair or save time spent in our reception. Note that most of these instructions are for iOS devices as they have more security-related settings. 1. Back up your data Please be sure to back up the data on your iPhone, iPad or Mac. If you haven't backed up your device yet, it may take longer to do the first backup. It is better to try while you're at home. Learn how to back up your iOS device or a Mac. Under some circumstances, during repairs of iOS devices, we...

Update: please check out this up-to-date Apple support article on how to Turn off Find My on your devices and items. When you bring your iOS device to our shop, we ask you to erase it and turn of Find My iPhone (FMi) feature. It is because sometimes the repair concludes by swapping for a new or refurbished device. The best is to back up the device (using iCloud Backup, or a computer with iTunes), then turn off FMi with Settings > iCloud > Find My iPhone and the erase the whole device in Settings > General > Reset > Erase All Content and Settings....