Not really - a computer is made up of a set of components, which can have their own individual identifications: CPU has a serial number, the HDD can also, and the network card will have a unique ID in the form of a MAC address.
Unfortunately, PCs being PCs, all of these can be changed.
You can get each of the various elements and combine them to form an id code that is unique to that PC, but if a component gets changed because it breaks, then your software will sort working. This has happened to me before, and it has been enough for me to say "I will not buy any product from that supplier again - it causes too much hassle".
If you want to go down this route, then look at
WMI[
^] in google or MSDN
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