Welcome to the Microsoft Community.
It seems that you are facing issues with networking Windows SP and Windows 8 computer. It would be great if you can answer the following questions:
Do you get any error message? If yes, what is the complete and exact error message?
Are both the computers on the same workgroup?
I would suggest you to refer to the articles and check if it helps:
Wired and wireless network problems
Why can’t I connect to a network?
You may refer to the articles and check if it helps:
Why can't I connect to other PCs?
Join or create a workgroup
Hope this helps. If you have any further issues on the computer, please post your question regarding Windows and we will be happy to help you.
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