If it has been 7 years, and apparently when you found out about it, (which seems like some time ago) and still haven't done anything, probably not.
However, if you were "never" served with the summons and complaint, and can "prove it," then you can set aside the judgment. Otherwise, too much time has passed. Courts like finality; they will not set aside a judgment without a solid reason (e.g. you weren't actually served and therefore the court lacked jurisdiction to hear the matter).
However, given the length of time that has passed since the judgment was entered, you will probably be fighting an uphill battle. If you plan to pursue the course of action described above, I recommend that you consult with an attorney in your area who can advise you on the strengths of your case and your state’s Code of Civil Procedure.
It is probably to long after the judgment to go back to present any new matters, you may be able to discharge this in a bankruptcy, if you qualify, or you can seek settlement to end this.
General legal advice is offered for educational purposes only. A consultation with a qualified attorney is required to determine specific legal advice as to your situation and applicable law. We are a debt relief agency and we help people file for relief under the bankruptcy laws.
Your only defense is to prove you were never properly served. Very difficult. Facts don't matter at this point. Only bringing case to lawyer is an option for review. If you were served can't retry case and negotiating a settlement or bankruptcy are options to pay less than full amount.
This is not to be considered legal advise and no attorney client has been established.