Check the status of the will by an inquiry to the clerk of probate court. This should be done as soon as possible after the death of the testator (the individual who executed the will). If the court has already made a grant of probate to the executor of the will, then your claim against it becomes more difficult, although not impossible.
File a petition in probate court to commence your action. State your grounds for contesting the will. In British Columbia, this may include improper execution, meaning the will was not properly signed or witnessed. Other grounds include the use of undue influence by one of the will’s beneficiaries, or the incapacity of the testator.
Prepare evidence supporting your allegations against the will. You may be able to prove undue influence through spoken or written testimony by witnesses; incapacity can be proven by medical records and evidence presented by treating physicians. You may prove improper execution through evidence in the will itself; for example, the signatures of the required two witnesses may be missing, or the will may not be in written form. Either circumstance invalidates the will in British Columbia.
Attend the probate hearing scheduled by the court to determine the validity of the will, and present your evidence to the court. If the court decides that the will is valid, you may still apply to have the will varied (changed) under the Wills Variation Act, but only if you are the surviving spouse or a child of any age of the testator. The deadline for such an action is six months from the date the will is admitted to probate. If the court accepts your petition under the Wills Variation Act, it may change the terms of the will