The White House will not identify a private company which appears to be involved in the disappearance of potentially millions of White House e-mails. The company was responsible for reviewing and archiving White House e-mails, a White House official told congressional staff in May, according to a letter yesterday from House Oversight and Government Reform Committee Chairman Henry Waxman, D-Calif. Congressional investigators asked then for the name of the company and "have repeatedly requested" the information since then, according to Waxman. They are still waiting for an answer, the chairman wrote to White House counsel Fred Fielding. Waxman asked the White House to come up with the company’s name by Sept. 10. White House spokesman Scott Stanzel declined to tell the Blotter on ABCNews.com the company’s name or explain why the White House would not provide it to Congress. "We are reviewing Rep. Waxman’s letter and will respond expeditiously," Stanzel said in an e-mailed statement. Click Here for Full Blotter Coverage. According to the White House, as many as five million e-mails may not have been properly archived and may be lost forever, in apparent violation of the Presidential Records Act. The post-Watergate law states that communications relating to official activity in the offices of the president and vice president are owned by the American public and cannot be destroyed. The unnamed firm "was responsible for the daily audits of the e-mail system and the e-mail archiving process," Waxman said a White House briefer had attested in a May meeting. The firm worked for the Information Assurance Directorate, under the White House chief information officer, Waxman said he was told. In addition to requesting the firm’s name, Waxman’s staff has also asked to see a White House report which detailed the days on which few or no e-mails were archived; the White House has been similarly unresponsive to that request, Waxman charged, and asked it provide the document by Sept. 10 as well. Do you have a tip for Brian Ross and the Investigative Team? This post has been revised.