If you're trying to add a student ID in Backpack and it's not being accepted, you're probably not doing anything wrong, it's likely just a mix-up between two different ID numbers your school has issued.
Why there are two numbers
Many schools give students two different identifiers:
A login or network ID: this is what you use to log into your student portal, email, and class platforms day to day. It's often alphanumeric, like "abc123."
A student or registrar ID: this is the number your school's financial aid and billing offices use to identify you, sometimes referred to as a "Banner ID." This is the number Backpack needs to match a payment to your account.
Because the login ID is the one you use constantly, it's an easy one to enter by mistake. Every school formats this ID a little differently, some are all numbers, some include letters or symbols, and the length varies too.
Where to find your correct student ID
Your school is always the best source of truth for this. The most reliable places to confirm it are:
Your student portal's profile or personal information page
The front of your physical student ID card
Admissions or financial aid correspondence from your school
If you're still not sure which number to use, or your ID keeps getting rejected, reach out to your school's registrar or financial aid office. They can confirm the exact student ID your school expects.