Monday 30 May 2016

Suddenly your Desktop shortcuts vanish

Applies to mostly all Windows 7 versions

You find yourself losing shortcuts on the sudden from your desktop.

Obviously the 'Windows devil' did its job :-) There's a service called System Maintenance troubleshooter which when it 'thinks' or indeed finds that you have broken shortcuts.

Broken shortcuts are those which apparently point to nowhere or the file, folder or application pointing at was either deleted or moved.

The System Maintenance troubleshooter performs a weekly maintenance of the operating system. It tries to either fix problems or report them to the 'action centre'. If it finds more than 4 broken shortcuts then removes all of them (broken).

To solve the problem you can either:

You can do something with your shortcuts with broken links to be at least 4 or less on your desktop. You can move all the rest to a folder on the desktop. The troubleshooter will not go in there.

But although Microsoft recommends to do something with your shortcut like above, you can always just 'shut down' the System Maintenance troubleshooter.

To do so,

1. Click on Start and then on Control Panel

If System and Security is not displayed you will need to change how you are viewing Control Panel. To change your view, click the down arrow in View by and select Category. View by is located in the top right corner of the Control Panel.
2. Under System and Security, click Find and fix problems.



3. On the left navigation pane, click Change settings.

4.  Set Computer Maintenance to Off.

Tuesday 24 May 2016

Wireless Signal Strength and Noise Levels

To make sure that all users in your environment receive a strong wireless signal, consider these guidelines when you install your AP devices.

Signal Strength

The signal strength is the wireless signal power level received by the wireless client.
  • Strong signal strength results in more reliable connections and higher speeds.
  • Signal strength is represented in -dBm format (0 to -100). This is the power ratio in decibels (dB) of the measured power referenced to one milliwatt.
  • The closer the value is to 0, the stronger the signal. For example, -41dBm is better signal strength than -61dBm.

Noise Level

The noise level indicates the amount of background noise in your environment.
  • If the noise level is too high, it can result in degraded strength and performance for your wireless signal strength.
  • Noise level is measured in -dBm format (0 to -100). This is the power ratio in decibels (dB) of the measured power referenced to one milliwatt.
  • The closer the value to 0, the greater the noise level.
  • Negative values indicate less background noise. For example, -96dBm is a lower noise level than -20dBm.

Signal to Noise Ratio

The signal-to-noise ratio (SNR) is the power ratio between the signal strength and the noise level.
  • This value is represented as a +dBm value.
  • In general, you should have a minimum of +25dBm signal-to-noise ratio. Lower values than +25dBm result in poor performance and speeds.
For example:
  • If you have a -41dBm signal strength, and a -50dBm noise level, this results in a poor signal-to-noise ratio of +9dBm.
  • If you have a -41dBm signal strength, and a -96dBm noise level, this results in an excellent signal-to-noise ratio of +55dBm.

(source: watchguard.com)