[syhprum (OP)]

I recently began to get messages that my drive was getting over full so I added up all the various sections and found only 50Gb.
I began to worry that I had been trojened and was acting as a server for kiddie porn or some such but I can find nothing untoward with any of the usual anti virus programs.
is this normall when running a 64 bit system on a rather old drive ?

[CliffordK]

No.

If you have a 64 bit OS, it has to be a reasonably new computer.  You should be able to have access to the entire drive, or at least 80% or 90% of it, so I would anticipate at least in excess of 200GB.

You can partition the drive.  Does Windows still support the DOS utility FDISK?  I wouldn't change anything with it, but it is good to at least poke around and look at things.

Some people like to separate "system" and "data" partitions.  There are some advantages of doing so, but inevitably one partition will grow out of proportion to the other, and you'll run into space issues with one partition, and not the other.

[RD]

Windows backup (system restore points) "https://secure.wikimedia.org/wikipedia/en/wiki/Shadow_Copy [Links inactive - To make links active and clickable, login or click here to register]" should only use up to 15% of the hard drive, but can use more if something goes wrong ...

http://www.howtogeek.com/howto/windows-vista/reduce-system-restores-disk-usage-in-vista/ [Links inactive - To make links active and clickable, login or click here to register]

http://www.howtogeek.com/howto/5482/make-system-restore-use-less-space-in-windows-7/ [Links inactive - To make links active and clickable, login or click here to register]

[syhprum (OP)]

It is my belief that it is often unproductive to try to sort out systems with obscure faults.
I used a Gordian knot technique and reformatted the drive and reloaded, rather laborious but never fails.

[RD]

It is my belief that it is often unproductive to try to sort out systems with obscure faults.

The native http://en.wikipedia.org/wiki/Disk_cleaner [Links inactive - To make links active and clickable, login or click here to register] utility would let you delete all but the last restore point.
If doing this freed up over 15% of your drive's total capacity then you'd know that's where the problem lies.

[graham.d]

My computer is also 64 bit but I don't have that problem. Are you adding up ALL the filesizes on the disk?

One thing I have found is that you should rarely trust what anyone says on any of the various forums on computer issues. It's impossible to extract the wheat from the chaff and 99% of it is chaff.

[CliffordK]

It's impossible to extract the wheat from the chaff and 99% of it is chaff.

That is a little harsh isn't it. 

I always try to deliver 100% high quality chaff in all of my posts!!!

[syhprum (OP)]

After reformatting etc I now have twice as much on the drive and it is only half full, there were ten files with long gobble de gook names that reported zero size that had appeared on the drive which I believe were due to some Trojan type take over as I have recently installed a wifi receiver device on the computer.

[Geezer]

were due to some Trojan type take over

Well, you know what they say -

"Beware of Geeks bearing gifts."

[graham.d]

were due to some Trojan type take over

Well, you know what they say -

"Beware of Geeks bearing gifts."

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