Photoshop 7.0 had no concept of "subscription" as far as I remember. You ARE talking about Adobe Photoshop 7.0, which came out what, about 15 years ago, right?
Can you please be more specific about the details? What do you mean by "sign in"? Exactly what are you starting, how are you starting it, and error messages are you getting? Screen grabs would be helpful.
Is this perhaps Photoshop Elements, which, IIRC, had the old, discontinued Adobe Photoshop.COM for additional Functional Content?
If so, then the very helpful and active Photoshop Elements Forum would be the place for your question. If you let us know the exact Adobe program, and it IS Photoshop Elements 7, then a MOD will gladly Move it for you.
Adobe Photoshop.COM has become Adobe Revel, and there is a special forum for that. I would start with the FAQ's sub-forum, IF this is related to PsE and Photoshop.COM: http://forums.adobe.com/community/revel/faq?view=discussions
Please let us know more about the exact Adobe program.