Translations by Joel Addison

Installed software

The software you use can normally be restored quite quickly after a serious computer problem by reinstalling it.

In general, you will want to back up files that are irreplaceable and files that require a great time investment to replace without a backup. If things are easy to replace, on the other hand, you may not want to use up disk space by having backups of them.

Advice on where to store your backups and what type of storage device to use.

You should store backup copies of your files somewhere separate from your computer - on an external hard disk, for example. That way, if the computer breaks, the backup will still be intact. For maximum security, you shouldn't keep the backup in the same building as your computer. If there is a fire or theft, both copies of the data could be lost if they are kept together.

It is important to choose an appropriate <em>backup medium</em> too. You need to store your backups on a device that has sufficient disk capacity for all of the backed-up files.

USB memory key (low capacity)

Internal disk drive (high capacity)

External hard disk (typically high capacity)

Network-connected drive (high capacity)

File/backup server (high capacity)

Writable CDs or DVDs (low/medium capacity)

Online backup service (<link href="http://aws.amazon.com/s3/">Amazon S3</link> or <link href="https://one.ubuntu.com/">Ubuntu One</link>, for example; capacity depends on price)

Some of these options have sufficient capacity to allow for a backup of every file on your system, also known as a <em>complete system backup</em>.

Why, what, where and how of backups.

<em>Backing up</em> your files simply means making a copy of them for safekeeping. This is done in case the original files become unusable due to loss or corruption. These copies can be used to restore the original data in the event of loss. Copies should be stored on a different device from the original files. For example, you may use a USB drive, an external hard drive, a CD/DVD, or an off-site service.

The best way to back up your files is to do so regularly, keeping the copies off-site and (possibly) encrypted.

<link xref="bluetooth-connect-device">Connect</link>, <link xref="bluetooth-send-file">send files</link>, <link xref="bluetooth-turn-on-off">turn on and off</link>…

Bluetooth is a wireless protocol that allows you to connect many different types of devices to your computer. Bluetooth is commonly used for headsets and input devices like mice and keyboards. You can also use Bluetooth to <link xref="bluetooth-send-file">send files between devices</link>, such as from your computer to your cell phone.

Bluetooth problems

Problems

Paul W. Frields

Connect your computer to a Bluetooth device

Before you can use a Bluetooth device like a mouse or a headset, you first need to connect your computer to the device. This is also called pairing the Bluetooth devices.

Before you begin, make sure Bluetooth is enabled on your computer. See <link xref="bluetooth-turn-on-off"/>.

Click the Bluetooth icon in the menu bar and select <gui>Set Up New Device</gui>.

Click the Bluetooth icon on the top bar and select <gui>Set up a New Device</gui>.

Make the other Bluetooth device <link xref="bluetooth-visibility">discoverable or visible</link> and place it within 10 meters (about 33 feet) of your computer. Click <gui>Continue</gui>. Your computer will begin searching for devices.

If there are too many devices listed, use the <gui>Device type</gui> drop-down to display only a single type of device in the list.

Click <gui>PIN options</gui> to set how a PIN will be delivered to the other device.

Choose an appropriate PIN setting for your device, then click <gui>Close</gui>.

Click <gui>Continue</gui> to proceed. If you did not choose a preset PIN, the PIN will be displayed on the screen.

If required, confirm the PIN on your other device. The device should show you the PIN you see on your computer screen, or may prompt you to enter the PIN. Confirm the PIN on the device, then click <gui>Matches</gui>.

You need to finish your entry within about 20 seconds on most devices, or the connection will not be completed. If that happens, return to the device list and start again.

A message appears when the connection successfully completes. Click <gui>Close</gui>.

I can't connect my Bluetooth device

There are a number of reasons why you may not be able to connect to a Bluetooth device, such as a phone or headset.

Some Bluetooth devices block connections by default, or require you to change a setting to allow connections to be made. Make sure that your device is set up to allow connections.

Your Bluetooth adapter/dongle may not have been recognized by the computer. This could be because <link xref="hardware-driver">drivers</link> for the adapter aren't installed. Some Bluetooth adapters aren't supported on Linux, so you may not be able to get the right drivers for them. In this case, you will probably have to get a different Bluetooth adapter.

Make sure that your Bluetooth adapter is switched on. Click the Bluetooth icon in the <gui>menu bar</gui> and check that it's not <link xref="bluetooth-turn-on-off">disabled</link>.

Make sure that your Bluetooth adapter is switched on. Click the Bluetooth icon on the top bar and check that it's not <link xref="bluetooth-turn-on-off">disabled</link>.

Check that Bluetooth is turned on on the device you're trying to connect to. For example, if you're trying to connect to a phone, make sure that it's not in airplane mode.

Click the Bluetooth icon on the top bar and select <gui>Bluetooth Settings</gui>.

You can send files to connected Bluetooth devices, such as some mobile phones or other computers. Some types of devices don't allow the transfer of files, or specific types of files. You can send files in one of three ways: using the Bluetooth icon on the top bar, from the Bluetooth settings window, or directly from the file manager.

Click the Bluetooth icon on the top bar and select <gui>Send Files to Device</gui>.

You can turn Bluetooth on to use Bluetooth devices and send and receive files, but turn it off to conserve power. To turn Bluetooth on, click the Bluetooth icon on the top bar and switch <gui>Bluetooth</gui> on.

To turn Bluetooth off, click the Bluetooth icon and switch <gui>Bluetooth</gui> off.

If calibration hardware is connected the <gui>Calibrate…</gui> button will create a new profile.

You will need to crop the TIFF file so that just the target is visible. Ensure the white or black borders are still visible. Calibration will not work if the image is upside-down or is distorted by a large amount.

The resulting profile is only valid under the lighting condition that you acquired the original image from. This means you might need to profile several times for <em>studio</em>, <em>bright sunlight</em> and <em>cloudy</em> lighting conditions.