If you feel the need to reformat your Mac, and I guess you have a good reason, then go ahead and do it.
The Mac OS does not have serial numbers, which explains why you cannot find them.
Just reformat and install and off you go.
Good luck
P
Hi I'm running osx 10.4 on a Macbook and am going to reformat. I have my original CDs but can't find their serial numbers if they came with them. I don't want to reformat and then get stuck being unable to reinstall the program. What should I do?

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