Link Safe

If other people regularly use your computer and plug in their USB sticks containing their own files, they could infect your computer by inadvertently transferring malware. Your anti-virus software should automatically scan for malware whenever a USB drive is plugged in. If it doesn’t, right-click the drive in My Computer and click ‘Scan for viruses’.

Alternatively, use the free Panda Research USB Vaccine (http:/www./Panda-USB-Vaccine.shtml) to

prevent malware on USB sticks installing on your PC. Once USB Vaccine is installed click ‘Vaccinate computer’ to disable theWindows autorun feature for USB sticks and CD/DVDs, so any malicious software stored on these devices won’t be able to install. To disable autorun on specific USB sticks instead, plug in the USB drive, select it from USB Vaccine’s dropdown device list, then.

You can carry your password with you in the form of a key. Predator (www.predator-usb.com) turns a USB stick into a clever password. This means you don’t need to remember complex passwords, but you mustn’t lose the USB stick. Once Predator is installed you’ll see a basic black and orange interface. The program’s default settings are mostly fine but you should change Read Interval from 30 to 5 so Predator checks for the USB stick’s presence every five seconds. If Predator doesn’t detect the USB stick, the computer will lock.

To set up Predator on a USB stick, type a password in the New Password field and tick Always Required. Insert the USB stick you want to use as a password and select it in the ‘Create key on Drive’ dropdown box. Click Create Key, then OK. Predator will restart your PC to complete the process. Once it’s restarted, click OK, launch Predator and it will minimise to the System Tray. It will now run every time you turn on your computer, so once it’s configured you don’t need to worry about it.

Just remove the USB stick to lock your computer. If you lose the USB stick, you can unlock your computer by left-clicking anywhere and pressing Enter on the keyboard three times. Type your

Predator password to access your computer again. To use Predator as a physical login you’ll need to set it up again as before.

Predator works brilliantly in Windows XP, Vista and 7 and is a great way of preventing access to your

computer. However, on Windows 8 it doesn’t disable the touchscreen. When we tried it we were still able to swipe to open the Charms bar and access our apps, though we couldn’t access the Desktop.

Google’s Nexus tablet is proving hugely popular. It was a total sell-out over Christmas, with analysts reckoning that Google’s first Android tablet has far exceeded the company’s sales targets. This success shouldn’t be a surprise, because Nexus tablets are attractive, well built, affordable and easy to use. However, many people barely tap beyond the first page of colourful icons and basic controls within apps. If you own a Nexus, you may be overlooking loads of exciting hidden features. So read on to discover eight secrets about your tablet - including some that Google has only just added.

To make sure you have access to the latest features, check that your Nexus is completely up to date. Tap the Settings icon from the Home screen, then scroll down to the System section and tap ‘About tablet’. Look for the version number, under the Android version heading. At the time of writing, the latest version is 4.2.2 (aka Jelly Bean). If your device shows a lower version number, or to simply check for newer versions, tap ‘System updates’ and then tap ‘Check now’. If a newer version is found, follow the prompts to update your Nexus.

With Android 4.2.2 installed you’ll have access to new features. For example, some icons in the Quick Settings panel can now be toggled on or off with a long press. To try it, open Quick Settings by swiping down from the top-right of the screen, then tap and hold the Wi-Fi icon to toggle it on or off. This same trick also works on the Bluetooth icon.

Another improvement in Android 4.2.2 is notifications, particularly when downloading apps. To see what we mean, start an app downloading then swipe down from the top-left of the screen to open the Notifications panel  notice that downloads in progress now include a percentage and estimated time before completion. But there’s more. If you tap the app download’s entry in the Notifications panel you’ll instantly flip to the Installed tab of the Google Play store, where you’ll find a Stop button. Tap this and all current downloads will be cancelled - a fast way to stop accidental installations.

While some websites allow you to view a desktop version of the site, others now force you to view the mobile version and that can render the Nexus’s pinch-to-zoom ability useless. But you can use Android 4.2.2’s accessibility features to get around this tap settings from the Home screen, then scroll down to the System section and tap Accessibility. Now tap ‘Magnification gestures’, flip the switch to the On position, then triple-tap to zoom in on anything, including mobile websites. Pinch as usual to alter the zoom level, or drag two fingers across the screen to pan the view. To exit this mode, triple- tap again.

In Android 4.2, Google has added a new feature called Daydream. This allows personalised apps to display information, such as favourite photos and local news reports, when the Nexus is docked or plugged in for charging - but you must first enable it and then set up what it should display, and which apps will use it. Tap Settings followed by Display then Daydream. Tap the switch to turn it on and then tap When To Daydream - the Either option is a sensible choice here. Now tap an app’s entry, then its Settings icon (to the right) to decide what it can display. Dock or charge your Nexus to see the Daydream screen.

Google has added several new features to the Gmail app that’s preinstalled on Nexus tablets. For starters, it’s now possible to remove an email conversation or message without deleting it. To do this, tap to select the message, then tap the top-right Menu button (three dots) and choose Mute- the message will disappear from the inbox but it will remain accessible (with an All Mail label). Alternatively, messages can now be deleted simply by swiping left or right across their inbox entry. If you change your mind, just tap Undo before you tap anywhere else on the screen. To add a confirmation before you delete something, tap the Menu button, select Settings followed by ‘General settings’, and then tap to tick ‘Confirm before deleting’.

If an app is misbehaving - or you’re curious to see what it’s doing behind the scenes - tap the bottom-right Recents button (two stacked rectangles), then press and hold the app’s entry. When the pop-up menu appears, tap ‘App info’. From here you can force the app to close (tap ‘Force stop’), disable it entirely (thus preventing it from working at all -tap Disable), or swipe up to see what the app does on your Nexus and the personal data it stores.

You may already know that swiping up from the Home button will open the Google app. Though ostensibly just a front end for the Google search engine, this app actually has an incredibly powerful hidden feature, called Google Now. This displays information ‘cards’ based on what Google knows about you, from a local weather forecast to directions to a forthcoming birthday party, say. To enable it, tap the bottom-right Menu button (three dots), then tap Settings followed by Google Now. Tap the top-right switch to turn it on then tap ‘Yes, I’m in’ to opt in (you are essentially agreeing to let Google scan your emails and calendar and know the location of your Nexus). Tap Settings again, followed by Google Now and you’ll be able to tailor precisely what information is displayed on the Google app’s Home page.

Speed up copying to USB devices If you want to copy files to USB drives in less time, try turning on write caching. To activate this feature in Windows 7 or 8, right-click Computer and select Properties. Click the Device Manager link on the left. Expand the Disk Drives section, right-click your drive, select Properties and go to the Policies tab. Tick 'Enable write caching on the disk' (or device) and click OK. Although you should get a small but noticeable speed increase by enabling write caching, there is a potential downside. If your computer powers down, or you unplug the drive before the data is written, it will be lost for good. You need to remember to always eject  the drive via the System Tray icon before physically removing it.

This happens because of a technology called Dynamic Adaptive Streaming over HTTP (DASH), which YouTube uses to deliver video more efficiently (at least from its perspective). But while it saves YouTube the trouble of having to deliver data that someone might not watch, it causes problems for people like you, who have very slow connections. is to disable DASH. The problem is YouTube won’t let you do that. However, it is possible to do it in Chrome using a free add-on called YouTubeOptions (https://chrome.google.com/Youtube). With YouTube Options installed, click the Chrome menu button at the top right (three horizontal lines), then Settings followed by Extensions. Next, find YouTube Options in the list and click the Options link. Scroll down to the Playback section and tick the Disable DASH box.

Note that YouTube Options’ default settings also disable various other aspects of YouTube, including adverts and captions so YouTube will look rather different next time you visit. Just return to YouTube Options’ Options page to explore and tweak these settings.