I lost my Office Home and Student version and want it back on the same computer

I had Office 2010 on an older laptop. When I upgraded the operating system, I lost my Office 2010 Home and Student version. It indicates on the “Office Product Key Card” that it’s for 1 preloaded PC only. This is still the same computer that it was initially installed on. How can I reinstall it without a disk or is this not possible?