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- Check that the computer is capable of running your desired version of Windows 7
- System requirements http://windows.microsoft.com/en-us/windows7/products/system-requirements
- Dell compatibility guide http://www.dell.com/support/troubleshooting/us/en/19/KCS/KcsArticles/ArticleView?docid=273634
- Lenovo compatibility guide http://support.lenovo.com/en_US/detail.page?DocID=HT003754
- See your manufacturers support site to see if they have drivers for Windows 7
- Make sure your software will work in Windows 7
- Make sure you have installers (CD's, downloads etc) and licenses (serial numbers, license files, etc) for your software
- Make a note of where data is installed on the computer
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