British workers spend up to an hour a day clearing their inboxes of junk e-mails, according to research.
Spam affects almost all office workers
Personal messages between staff are also eating into work time at small firms, the survey suggested.
The University of Nottingham study said almost all office workers are affected by the daily arrival of unsolicited and unwanted e-mails.
It also found that almost half of small firms continued to favour face-to-face meetings above conference calls.
The university's Institute for Enterprise and Innovation said a third of respondents to their survey believed staff spent
60 minutes per day dealing with unwanted e-mails.
Almost a fifth of the 174 businesses contacted claimed that they lost more than an hour as staff dealt with the problem.
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One respondent said: "E-mail has become the bane of all of our business lives.
"It is the memo of this century that everyone hides behind, I truly hate it."
The study was carried out as part of the UK Business Barometer, a project to provide better information about small companies.
A spokeswoman for the institute said: "We undertook the survey following reports that some large companies and organisations have introduced measures to reduce the volumes of e-mails sent and received by staff.
"New European laws also came into force in early December, the first step towards banning the sending of spam."