A week without e-mail is more traumatic than moving house or getting divorced, say techies.
How does this compare to losing e-mail for a week?
The findings come in a survey of information technology managers for the software storage firm Veritas which looked at how businesses have become dependent on e-mail.
Electronic mail is playing such a key role in companies that most people start to get annoyed after just 30 minutes without e-mail access, the study found.
But spare a thought for the techies in computer support. About a fifth feared for their jobs if they did not get the e-mail system back up and running within a day.
More than 800 techies in Europe and the Middle East were quizzed about the role of e-mail for the survey.
"E-mail has become far more than a communication tool, placing a huge responsibility on organisations to ensure that e-mail is always available," said Mark Bregman of Veritas.
"When information technology managers fail to keep the systems running, they inhibit the ability of the entire organisation to conduct business."
On the positive side, 99% of companies regularly back up e-mail and attachments.
But finding a specific message among thousands is trickier.
Which cable will restore the e-mail system?
About half of the managers quizzed said it would be difficult to locate and retrieve a particular e-mail on the system.
And tracking down an old message could be virtually impossible. Only a fifth said they could recover an e-mail from further back than a year.
According to Veritas, the survey shows "alarming deficiencies in current e-mail system management and backup and recovery methods, placing businesses at risk and causing undue stress in the workplace."
And when something goes wrong with e-mail for a week, the experience can be more traumatic that moving home, getting married or divorce, at least for a third of those taking part in the survey.