* Windsor Group of Reston has agreed to be purchased by BB&T Capital Markets of Richmond. Terms were not disclosed. Windsor Group is a 14-year-old investment bank that provides merger and acquisition, valuation, and corporate finance services. Many of its client companies are government contractors in information technology and defense. BB&T said Windsor Group's staff of 17 investment bankers, including co-chief executives J. Richard Knop and John C. Allen, will join BB&T Capital Markets. The acquiring company is owned by BB&T Corp. of Winston-Salem, N.C., which is also the parent of BB&T Bank.

* USA Mobility of Alexandria said the merger of its constituent companies, Metrocall Holdings and Arch Wireless, is complete, combining the nation's two leading companies that market paging devices. Vincent D. Kelly, president and chief executive, said in a statement that the merger brings together the strengths of the two companies even as "the paging industry has continued to shrink due to considerable competitive pressure" from cell phones and other wireless technology. USA Mobility said its stock will trade on the Nasdaq National Market under the ticker symbol USMO.

* Avatech Solutions, an Owings Mills company that sells design automation software, lost $813,448 (9 cents a share) on $6.8 million in revenue during its first fiscal quarter, compared with a loss of $503,476 (6 cents) on $5.9 million in revenue during the same quarter ended Sept. 30 last year. Shares fell 5 cents to close at 38 cents.