Denial Of Service Attacks (DoS)

In DoS attacks, the attacker attempts to overload or shut down a system so that users can no longer access it. Most frequently web servers are targetted in order to make websites unavailable. The main target is not to steal or compromise data but to interrupt a web service which can prove costly for some organisations and companies.

These types of attacks involve sending more traffic to a system than it can handle. This can be performed by sending oversized data packets, sending email attachments which longer names than supported by mail programs, sending IP ping messages that seem to originate from the victim computer to a large number of computers (victim is flooded with responses afterwards).

A Distructed Denial of Service attack (DDoS) attack uses a large number of computers (usually part of a zombie network - computers that are compromised and controlled by hackers by using a virus or trojan) to launch the attack.

Phising

Creating secure passwords is essential nowadays with the spread of cybercrime increasing daily.

Here we will give you some 'golden rules' on Password Selection and some 'methods' that could help you achieve that.

Your password should

1)  Be 8 or more characters.

2)  Contain letters (lowercase and uppercase), numbers, punctuation and symbols.

The greater the variety of characters the better.

Electrical/Electronic Failure

The printed circuit board (PCB) of a hard drive controls and coordinates the communication between the computer and the hard drive in order to read and write data. So, when it gets damaged (mostly due to surges or power spikes) you lose access to your data. More often than not other hard drive components are affected as well such as the read-write heads and pre-amplified circuit.

Signs of electrical/electronic failure are:

• Drive is powered, but shows as if not functioning (platters not spinning)
• Disk knocking as the motor fails to spin
• Repeated clicking sound as the heads search or initialize

Determining the failure of your hard drive is not always straightforward. Some types of failures are obvious to detect and others not. Some very common signs that your hard drive is failing are:

Loud Noises: If your drive makes unusual noises such as clicking, grinding, scraping or emitting a very high-pitched whine, then this is a clear indication that your drive is either soon failing or has already failed.

Not recognised: If your hard drive is not recognised at all in BIOS during boot time, while it used to in the past, that is also and indication of some sort of hard drive failure.

Smart Indication: If your hard drive supports the Self-Monitoring, Analysis and Reporting Technology (SMART), then any indication of a SMART error while booting your computer is a clear sign that your hard drive is failing.

It is very common that laptop owners experience their laptop overheating. Some signs that this is the case are when your laptop suddenly shuts down after operating it for a certain amount of time and its casing become increasingly hot as you operate it. Most of the time, the cause is dust accumulating to the cooling fans and the heatsink which in turn causes the processor to overheat and the bios shutting down the computer in order to protect the CPU.

If you can hear the laptop's fan spinning it is a good sign that it is working and that a replacement would not be a neccessity (something that would require dissasembling the laptop and replacing it). A complex and risky procedure to try without the help of an expert (Computer Repair London) .

However, before resorting to bringing to us you can try the following tips:

1) Unblock the air flow by blowing into the laptops exhaust  (from the bottom and side) with a compressed air can .

2) Keep the laptop on a flat and hard surface. When the laptop is placed on an uneven surface such as a pillow or blanket the flow of air is disrupted and the laptop overheats. You can avoid that by placing it on a tray or a special laptop holder or stand.

Below we are describing how to remove your hard drive in order to send it to us for data recovery purposes.

1) First turn off your computer and remove all cables. Before removing the power cable, touch the side of the metal case to discharge any static which may have built up on your body.The majority of computer cases are secured using screws. The removal of these allows access to the inside of the case. Below is an example of a case with "side doors". Only one of these needs to be removed to access the drive. Depending on where your drive sits inside the case you may need to remove both the left and right side doors.

2) Identify the hard disc, which will have two connections - data and power. Appearance will vary depending on whether it is an IDE drive or a SATA drive. Carefully slide out both connections taking care not to damage the cables. On IDE drives, the power connector will be in quite firmly . The first image below is an IDE drive and in the second a SATA Drive.

Delete Temporary Files

There is a variety of temporary files residing in your PC which take up a lot of space and slow it down. These can be Temporary Internet Files, Windows Temp Folder, Log Files and others.

The location of these files varies from one Windows version to the other, thus it is much preferable to use a free utility in order to remove them.

Windows does provide such a utility called Disk Cleanup (In Windows XP go to Start -> All Programs ->System Tools->Disk Cleanup). A better alternative would be CCleaner which can be downloaded for free.

Defragment your hard drive