This click is the head assembly moving back to its home position (park), recalibrating itself and then coming back out to attempt another pass, over and over. This process is a loop, not a one-off failure, and each time through the loop costs you something. Power it down before reading the rest of this.
The drive can't read its servo information and thus returns the heads to their home position and attempts it again. If there is damage to the heads, each of these trips will bring the heads back across the surface containing your data.
Each and every time you have a clicking drive, you're told exactly what has happened. The heads can't read the servo info (the positioning information written across the platters), which tells them where they are. So, as soon as they can't read that info, the actuator withdraws to its park point and comes back out. And that withdrawal is the click you hear.
It continues to occur because the drive will keep attempting to access. Each load of the heads places them directly on a surface they may already be contacting; where contact is occurring, each time they pass over, they remove a little more of the magnetic coating your files are written on.
That's why all of the advice given concerning this issue is always the same, and always urgent: turn it off. Not when you finish what you're working on. Now.
The entire rest of the recovery process depends upon the type of failure. However, this part depends on you, and your actions make more of a difference to the final results than anything done afterwards.
If you switch the drive off immediately upon hearing the very first unusual noise, most likely you'll recover virtually all of your lost information. A hard drive which continued to run for a couple of weeks while someone hoped it would eventually quit making weird noises will frequently recover only partial amounts of information, due to scoring damage to the disk that cannot be repaired: the physical layer that held that data has been destroyed.
There is no technology, lab or price that can restore a scored surface. That is the one truly irreversible outcome in this work, and it is almost always self-inflicted after the fact instead of being caused by the initial failure.
No, it is the same fault. Instead of continuously retrying, this unit attempts to initialise, fails and simply stops trying. The heads have still been in contact.
Please do not. Scanning causes the failing drive to remain powered and “seeking” for hours, which is exactly what will cause a partial failure to become complete.
No. This is thirty-year-old advice from a bygone era of engineering, and applying such methods to a modern hard drive will introduce condensation into a sealed assembly with sub-micron head clearances. In fact, this method has ended what otherwise would have been routine recoveries.
No. A drive that has had replacement parts installed is a single-use device to read data off once. Anybody who claims you can install replacement parts onto a failed unit and then expect it to be reliable enough to be used again is describing something that does not exist.
This depends almost exclusively on how long it continued running after the initial click occurred. You get an honest estimate at the free diagnostic rather than afterwards.
From £300 +VAT for mechanical work. A 50% deposit is required as both bench time and donor parts are committed at the start.