Appeal from a decision of the Unemployment Insurance Appeal Board, filed October 9, 2003, which ruled that claimant was disqualified from receiving unemployment insurance benefits because her employment was terminated due to misconduct.
Substantial evidence supports the decision of the Unemployment Insurance Appeal Board ruling that claimant lost her employment as a customer service representative due to disqualifying misconduct. The record establishes that claimant violated the employer’s policy regarding the electronic communication system by forwarding a personal e-mail to half of the company employees while on the telephone with a customer. The record also evidences that claimant put the customer on hold in order to send the e-mail and then asked the customer to repeat information which already had been relayed. Inasmuch as a knowing violation of an employer’s established policy or *879workplace rules may constitute disqualifying misconduct (see Matter of Dzaba [Commissioner of Labor], 6 AD3d 907 [2004]; Matter of Graham [Commissioner of Labor], 305 AD2d 922 [2003]), the Board’s decision will not be disturbed. A recording of the telephone call and claimant’s computer screen indicated that she, in fact, sent the e-mail, and her assertion to the contrary presented a credibility issue for the Board to resolve (see Matter of Livadas [Commissioner of Labor], 3 AD3d 656 [2004]).
Mercure, J.P., Spain, Carpinello, Rose and Lahtinen, JJ., concur. Ordered that the decision is affirmed, without costs.