Sorry you're stuck but there's almost always a pretty easy fix! Do NOT try to start all over again, eg. uninstall Max's Pitch Package, etc. That can make things worse.
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Hello,
I completed max labs 3a/3b but I cant use the grading software because it says that my sales force account is too old (im using the same account from a previous semester). I also tried making a whole new email and sales force account but now it will not allow me to install the tool to the new account.
I see. You’re still logging into the old account that already had the grading app. That’s why it’s saying you can’t upgrade. You need to log into your nee account. Be sure to use the new Username and pw. Maybe open a private/incognito window and just enter login.salesforce.com and go from there.