Software maker Concord Communications ( CCRD ) was hit hard Monday after the company warned about first-quarter earnings. The Massachusetts-based company said it expected a loss of 3 cents to 5 cents a share on revenue of $23.5 million and $23.8 million, as the company said it was unable to complete negotiations on several deals in time for the close of quarterly business. The consensus estimates of analysts were for a profit of 10 cents a share and revenue of $27.9 million for the quarter ended March 31, according to Thomson First Call. Shares fell $2.53, or 18%, to $11.50 in premarket trading. Concord also said second-quarter revenue is expected to be between $25 million and $30 million. The consensus estimate is for $29.1 million. The company will update guidance when it releases first-quarter results April 14.