**LINK**

Ah, Bob – we're just gently pulling your leg, of course…!

To really find out what is going on you need to do a lot more work.

This is, of course, a very small subset of all the RFCs which apply to internet communications generally. There must be the best part of 10,000 by now,

Once you have read and understood all the RFCs, you then need to examine all the different software packages which incorporate them and are used by the different service providers. Finally, you need to find out how these are set up and used at the different nodes through which your message passes, and what glitches have recently been experienced which may have caused a rejection or resend…

Alternatively, you could just trace the paths of the emails you are curious about. Here are a couple of links which give you a bit more information:

**LINK**

**LINK**

..and, if you want some automated help: **LINK**

As an aside things that are erased on any computer system are rarely actually erased.  Data on a computer is usually held like a poem in a book – written on a page somewhere, with a pointer to it written in the index.  To delete an item, the pointer is the only thing that is usually deleted, and the space that the pointer pointed to is reclassed as 'usable'. Only when that space is overwritten with something new does the original data disappear (though even then you may be able to get something back if you are willing to do something clever, technical and highly expensive..)

The reason for this is that data is only deleted if it is overwritten, and overwriting takes as long as it did to write the item in the first place. For a big file that can take many minutes – much easier simply to mark it as 'gone'.

If something has been deleted and lost all its indexing, since photos, Word files, and many other bits of data have standard headers, you can read across a whole disk and find these headers – then read along until you find an 'end-of-file' marker, and recreate that as a new file. Often that will be an original file 'deleted' years ago.  If you have only just deleted the file, it might even be possible to recover the original index data from a local store, which would be even quicker.  Forensic tools use this facility to recover deleted data, which is why Hilary Clinton has been using a specific overwrite facility –  BleachBit – on emails she didn't want the FBI to find…

Edited By Dodgy Geezer on 28/09/2016 12:02:05

Edited By Dodgy Geezer on 28/09/2016 13:16:16

Bob

The problem with your computer is easily solved.

Remove the back cover with one of those tiny screwdrivers and carefully remove the dead hamster then replace with a fresh one………….problem solved.

Paul

Bob,

It is indeed still full of data — and fairly easliy recovered data even without tons of expertise or expensive tools — unless you have done a true delete.

When you empty the wastebin of your computer, all you really do is remove links to the underlying file. For a full delete, the disk space used to store the data in question must also be overwritten with new, random data, ideally several times.

On a Mac, which is what I use, the system comes with such a possibility inbuilt; I don't know what goes under Windows, but if it is not included, there should be freeware available out there that will do the job for you.

Of course, if you are talking truly sensitive data (like the secret inner workings of the Abell drive for example) you should probably also expose the hard disk to some very serious magnetic fileds and then have it physically shredded (yes, there are services that will shred a hard disk for you!) but for the common or garden variety of data, a number of dlete-and-rewrites should be mpore than sufficient.

It can take half a day or more, though, if the hard disk is large, but for peace of mind, I've done it for the last few times that I upgraded my 'puter and gave the old one away to a charity shop or similar.

Mattias

I'm concerned that the Hard Disc is still full of Data?

That's about as safe as opening your front door wide and having a flood-lit sign saying "Help yourself to anything valuable here", Bob. Even erasing all of the files with a Windows command won't do much except make them a little more tricky to recover i.e. ten minutes work instead of five.

Remove the hard drive and either smash it to pieces with a hammer or drill three or four times vertically right through it. Before you do that, however, see if there are any useful little screws, springs, motors etc which you can salvage.

As regards the phone, I'm led to believe that all of the personal data is held on the SIMM card – but I'm happy to be corrected.

Dave M

I don't hold sensitive information on my phone but a complete reset will usually erase everything. plus, as Dave says, remove and destroy the SIM card (preferably after you have transferred your contacts to the new phone).

As far as hard disks are concerned, they are remarkably robust when you want to destroy them. I drill holes into the casing and pour old paint or something corrosive into the innards, I then use a club hammer on the case.

Similar methods applied to your own memory could result in a murder charge for someone.

Colin

Hitting things hard wiv an 'ammer can be a dangerous activity if things break off, and drilling can be an arduous activity if you hit the hard internal magnets…but try it if you like. My approach is:

1 – Do a risk analysis. What might have ever been put on that drive? Who is likely to attack it? If it's NATO crypto key material and you know there are dodgy geezers with snow on their boots going through your trash, go to 5

2 – Does the disk still work? If it works, and you don't want to use the computer any more, run an overwriting package. After you have done this the entire disk will be cleared, so don't expect to boot it again unless you do a rebuild. DBAN is a (free) favourite of mine – **LINK** . Hillary Clinton uses BleachBit – **LINK** . You only need to set these to one overwrite PLUS a validation read (to be sure it worked. After that you can sell the machine or give it away as a working machine (with no O/S) if you want.

Note that overwriting MUST be for the WHOLE DISK. Don't fiddle with trying to overwrite just the sensitive bits. There will always be some scrap of data unaccounted for somewhere…

3 – If the disk does not work, use a screwdriver to separate the two halves of the disk. Undo the central disk mount and remove the platters – there will be 1-4 of them. The inside of the disk also contains two strong magnets, a nice low-friction pivoting arm and some other goodies. If you don't want them, throw them into the bin.

4 – If the platters are a glass substrate, tapping them with a hammer will make them shatter. If they are a metal substrate, a blow-lamp (or any fire) will make them vaporise. Try it – it's fun. You can then bury the ashes or fragments…

5 – The above is fine for any data which is not targeted by a skilled attacker. For such a person/organisation, at considerable cost, it may be possible to extract data from an overwritten disk or a hammered and drilled disk, depending on a large number of variables. For such data, the disk platters need destroying in the controlled area where they reside. See me for further details!

Do not do what GCHQ used to do back in the 1980s, which is store all the sensitive data on site until they had a lorry load that they could take to the secure furnaces at Llantrissant (The Hole with the Mint in it). That way, disks go walkies from the store, and the lorry is an obvious target. Last I heard, they were using an acid bath at Rolls Royce, Derby… Oh, and none of the above applies to Solid State Disks…..

An old computer is full of useful bits. After it has been unused for a day or so, there is unlikely to be any juice left in the capacitors. Turning the system on when it's not plugged in frequently flattens any charge still left. The only ones which are big enough to store anything you would notice are going to be in the power supply, which is in a separate box.

The sheet metal sides of the power supply box are often a thin gauge, and really useful for modelling. The PCB inside has useful power diodes. If you are concerned about the capacitors, touch an old (insulated) screwdriver across the terminals. That will short it out.

Driller Killer Dave.

Colin

Yeah, DG….whatever.

DM

Bob

If you are worried about charged capacitors it would be a good move to unplug the computer from the mains before smashing it to bits with a sledge hammer (wooden handle of course)

Bob

Fair enough Bob but is there any more to be gained?

Paul