I would take this to the computer forum you might have more luck getting answers, at a glance it looks like you are missing drivers after re-installing XP or old drivers. Even a paid for driver checking program will not help if the driver is missing.
Open your control panel, then System, then Hardware, then Device Manager. That will list all of the hardware your software is aware of, see if you have warnings on anything. Look and make sure all the hardware you know you have shows up.
Then go to the vendor site for your PC first, and get the latest driver they provide for each thing and install it, if they don't have it go to the device maker and get the driver there and install it.
Once all your drivers are right then you can start on the S/W issues.
One last note, look in your control panel and make sure you have an icon for like "Sounds and Audio Devices" if not you need the MS driver, you can get that from MS, same for mouse, network connections, game controllers, etc...
Try "Add Hardware" and see if it finds things and so on. No need to spend any money yet...
After having problems with a possible virus and reinstallation of xp, I've now a few problems with hardware and software that couldnt be recognised. One noticeable one is the fact that it wont recognise speakers for audio codec. Are there any prgrams like "driver detective" that do not ask for yearly subsciptions or credit cards? If I am going to spend any more money, it would be on a new computer.

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