Network: Helpline; A mouse that doesn't roar

I have tried to change my analogue mouse to a ps2 mouse, using Windows 95. I bought an adapter (nine pin to PS2), changed via the Control panel/Mouse properties the mouse to a "Standard PS/2 Port Mouse", plugged the adapter in and rebooted. But nothing happened, it refused to acknowledge that a mouse was attached at all. I have tried other things, all to no avail. What do I need to do to get this mouse recognised? Is the adapter faulty?

I'm afraid I haven't heard of anyone plugging a serial mouse into a PS/2 port, as it's usually the other way round. One of our other staff members reports that he has tried it in the past, but couldn't get it to work, either. The only thing I can suggest is that you try a genuine PS/2 mouse to make sure that your PS/2 port is working - perhaps you can borrow one from a friend? Also, check that the PS/2 port is actually enabled in the PC's Bios - it could have been turned off if your vendor decided to ship a serial mouse with the computer instead.

Could anyone advise me if there is any way of obtaining a black cursor in Windows 95? I have difficulty seeing the standard outline pointer, even when extra large. A black cursor was available in Windows 3.1. It does seem odd that this appears to have been dropped from Windows 95, a product that claims to be more user friendly.

Neither Windows 95 nor Windows 98 has a solid black cursor, an alteration that does seem a little odd on a package that purports to offer increased user-friendliness. There are, however, a couple of solutions to your problem; the first is to upgrade to a mouse that offers additional cursor options; Microsoft's Intellimouse, for example, includes a large, dark grey cursor arrow with heavy black outline.

Alternatively, you could use a shareware or freeware cursor utilities package, such as Biggy, to alter the options available to you. Check out ZDNet UK's downloads library (http://www.zdnet.co.uk/ software/), where you will find a wide range of cursor utilities to turbo-charge your mouse.

Imagine if a car manufacturer advertised a car with 80- cubic-foot boot capacity, but when it arrived at its new owners the handbook actually said: "The boot is only 40-cubic-foot, but we think you can squeeze most stuff to half its original size, so let's call it 80. There would be public uproar! So how do tape-drive makers such as Hewlett-Packard get away with advertising "5Gb (2.5Gb native)" capacities?

The compression ratio of 2:1 is a guess, which is often wrong. It depends on the amount of redundancy in the data to begin with. Try putting 5Gb of ZIP or MPEG files on to one of these so-called 5Gb tapes and see how far you get. About 2.5Gb is how far you'll get, because that's how big the tapes are. Tape-makers, why don't you give us all a break and just advertise the real size like everyone else does?

You're quite right - the capacity of many tape drives and their media assumes a 2:1 compression ratio. This stems from the traditional use of tape as a backup and archive medium, where compression is almost invariably used. The 2:1 ratio is the worst case for files that don't contain a lot of redundancy (ZIP and MPEG files have NO redundancy because they are already compressed), so you should be able realistically to achieve it with everyday data. We can see that quoting the compressed capacity can be confusing, but it has now become standard practice, and as the manufacturers' usually quote the native capacity as well, they aren't attempting to deceive anyone.

Send your questions to Helpline, Network, The Independent, One Canada Square, Canary Wharf, London E14 5DL or e-mail them to network@independent.co.uk with Helpline in the subject field.

Daniel Robinson is technical editor of `PC Direct' magazine.