I assume you mean the Desktop program? No. Unless one is the Turbo Tax Business program (not Home & Business). You can have Turbo Tax Business and any Personal version installed at the same time.
Why do you need 2? All the Desktop programs have the same forms. You just get more help and guidance in the higher versions. The Desktop program can prepare unlimited returns.
Fyi - if you do another return for someone else like your child and their name is the same or similar to yours then it might overwrite your return. You have to save each return with different names so you can tell them apart. Like if your name is John and your son is also named John it will save them with the same name so the second one will overwrite the first return. Go to File-SaveAs and give it a unique name.
