Thank you both for your replies.
Peter: The Hard drive was brand new. It was installed by the firm that carries out Dell repairs under Dell's next business day warranty and was a result of my online chat with Dell and after running a diagnostics test. When I put the System Tag (not the new number) in the box it shows details of my warranty but when I ask to search for the tag it does not find it or my express service code, that is what concerns me.
Samuria: I think you have described it more or less correctly and I now believe that what I thought was a new tag number is, as you say, what they are calling the machine. Here is a little more information that may help:
Yes I am trying to connect to my network. Basically I have 3 laptops. When I transferred files previously over the wireless link my two other XP machines were displayed by their Service tag numbers. Since the new hard drive has been fitted to one of my machines it displays a different name or number, which I took to be the Service Tag, since when I tried to search for it's Service tag number on the Dell website it was unable to find it, so I assumed the new number displayed must be it's Service tag. When I search for information on this particular computer it does not show a Service Tag No or Express Code No, however when I go to Advanced Information this new name/number is displayed as 'System Name' and also as it's 'User Name'.
Whatever this new name or number is, when I click on it it requires a User Name and Password, so my latest idea was to put in the User Name that the advanced information gave, as that seems to be the most likely one, but I've no idea of a password so I have tried pretty well all the passwords I use but to no avail.
This current laptop is using Vista, but when I hit 'Network' it used to display the device by it's system tag number prior to one of the laptops having a new hard drive fitted. I can still send files to the other computer though, as I said, by pasting them into the 'Public' file on this 1720 computer and then accessing them on that computer.
I've tried creating an account on the other computer with the User Name, but it would not allow me to create it with what it called my computers name and I have tried creating a new account with a new password but that didn't work either.
I'm probably guilty of not fully describing what I mean but I would have thought there has to be a simple answer to this, but I'm darned if I can find it. At the end of the day I can still transfer the files by clicking on the Public icon, but I can't see why I can't access the icon for that particular laptop.
As an extra point I should add that I have Sky Player installed on that particular laptop and, as you may be aware, it is specific to one machine, it cannot be run on more than one computer per Sky account. When the new Hard Drive was installed and I dowloaded Sky player it said I was accessing it from a different computer, so I had to email Sky before it would work on this computer again. That's also why I thought I must have a new tag number, as Sky Player did not recognise the computer.
