Error of law: If a party enters into a contract without knowing the law of the land, the contract is affected by such errors, but it is not void. The reason is that ignorance of the law is not an excuse. However, if a party is mistakenly induced to enter into a contract, such a contract is not valid.  Illustration: Lady found a stone and sold it as topaz for $1 ($25 today). It was an uncut rough diamond worth $700 ($17,000 today). The contract is not questionable. There was no mistake, because none of the parties knew what the stone was.  The Record Retention and Correction Act was amended by the U.S. Court of International Trade in Hynix Semiconductor America, Inc.c.
United States, 414 F. Supp. 2d 1317 (I.C.T. 2006), in which the Court was confronted with the application of a customs tariff calculated by a customs officer at the wrong rate. In order to enforce “anti-dumping” legislation against foreign-made products (in this case, Korean electronic components) manufactured with cheap labor and undercut by U.S. industry, a regulatory system was introduced under which these imports were subject to a “liquidation duty” at a rate that could be found in a schedule. The timetable had been established by a group of experts using standards to adjust the price differential of overseas goods. The customs officer used the wrong category of goods and inflated the tax, and when Hynix found out what had happened, part of a very short statute of limitations for the protests had expired. However, Hynix prevailed and received the correction of its tariff rate with proof that such an error.” could be corrected under 19 U.S.C. § 1520(c), as an error of fact or writing which does not constitute an error in the interpretation of a law and because the absence of opposition within ninety days of the dissolution of the registrations is in that context without legal consequence … » Id. at 1319. As in the case of a unilateral error, if the unmarried party was aware or should have been aware of the error, the resulting contract is voidable for the wrong party.
For example: mistakes can be mutual, meaning that both parties shared the same erroneous assumption, or can be one-sided, meaning that only one party was under a false impression. Another breakdown of contract law divides errors into four traditional categories: unilateral error, mutual error, description of the missing person and misunderstanding.  This presentation will focus on several cases where the courts do not perform a contract even if it fulfills the basic contractual elements of the offer, acceptance and consideration. We will highlight the three “M`s”: errors, misunderstandings and misrepresentations. If only one party is wrong, the error is a “unilateral error” of the law. A unilateral error of law can only be withdrawn if the other party is aware of the annulling party`s legal error, but does not correct and exploit it or makes unfair claims against it. See Civ. Code § 1578 (2). For example, if a husband and wife have entered into a matrimonial settlement agreement based on a misunderstanding of the law on their lifelong property rights, and the husband has not corrected their misunderstanding or caused that misunderstanding by his own misconduct, the wife has the right to annul the marriage settlement agreement because of her unilateral error of law.
See e.B. Simmons v. Briggs (1924) 69 Cal. App. 447. A countervailable contract is a contract that a party may cancel or cause to be cancelled by a court. However, until the wrong party makes use of their right of withdrawal, the contract remains valid and legally binding. The consequence of withdrawal is that the contract is terminated and that the parties, as far as possible, are returned to their pre-contractual position. This means that neither party is able to sue the other party over the contract and that any payments made or assets transferred under the contract are recoverable because neither party is entitled to what they received.
Alternatively, if the contract is questionable, the contract is valid from the beginning and obligations may arise from it despite the error. The last type of error involves transmission errors through an intermediary. In particular, a contract is void at common law if the object of the contract no longer exists, for example a contract for .B purchase of goods if those goods have already disappeared. Similarly, the contract is void if the buyer enters into a contract for the purchase of something that already belongs to him. .