Prior to Probate
You can file a caveat with the probate court to block a will at any time up until it is delivered to the court for filing. A caveat is a written document that states the reasons you object to the will. You may have only a short amount of time to do so, however, depending on when the executor submits the will for probate. When she does, she will choose a method of probate. The method will dictate how much time you have left to challenge the will if you have not done so already.
Common Form Probate
If the executor requests common form probate for the will, you have four more years to contest it. Common form probate does not require that notices be sent to any heirs, beneficiaries or creditors that the will has entered probate. Therefore, a will probated in common form is not final until four years after the date it is received by the probate court, and you can object to it at any point during that time.
Solemn Form Probate
If you have filed a caveat with the probate court, the will automatically enters solemn form probate because its validity is being challenged. If you have not filed a caveat, your time to contest the will becomes severely limited if the executor chooses this option. He must file a petition with the court requesting this type of probate, and notice of that petition is sent to all interested parties. A hearing is held where the court rules conclusively on whether or not the will is valid. Therefore, if you don't appear at this hearing to object to the will and if you don't contest the will while it is in probate, you lose your right to do so after probate is closed.
The only exception to challenging a will after solemn form probate is if you should have received the notice of proceedings and you did not. Then you have four years to bring this to the court's attention, just as though the will was probated by common form. Anyone who wants to contest a will in common form probate but is unable to because he is a minor also has four more years to file a challenge after he reaches the age of majority.