The short answer
A default judgment is entered when a defendant does not appear or respond on time. Illinois allows defaults to be vacated, but the standard gets stricter the longer the defendant waits.
Where it fits in your case
After the response deadline passes without an appearance.
What to expect
Within 30 days of a final default judgment, a motion under 735 ILCS 5/2-1301(e) is judged liberally.
After 30 days, a petition under 735 ILCS 5/2-1401, filed within two years, requires a meritorious defense and diligence.
Void judgments, such as those entered without proper service, can be challenged at any time.
Damages usually still must be proven when the amount is not fixed.
What we need from you
The default order, every paper you received and when, and anything showing why the deadline was missed.
Common misconceptions
“A default is permanent.” It can often be undone, especially if you act quickly.
“The plaintiff gets whatever it asked for.” Damages that are not a fixed sum still need proof.