The survey, conducted by market research firm Harte-Hanks on behalf of MessageLabs, found that around 10% of working time per day is spent dealing with unsolicited e-mail. Three-quarters of respondents predicted that spam would be a "much" or "somewhat" bigger problem in the year ahead.
Along with affecting employee time and productivity, spam also uses up network bandwidth and storage space. According to MessageLabs, the problem is made worse by the fact that unlike with e-mail viruses, firms have difficulty determining what is and is not spam.
MessageLabs has launched an anti-spam service called SkyScan AS.
Jos White, founder and marketing director at MessageLabs said, "The problem is not only that it gets through, but that firms don't know how to define it - with viruses it is easy, but one man's spam is potentially another's useful information."