Manx Telecom is apologising to customers following failings with its e-mail service.
People have been complaining that outgoing mail hasn't been reaching its destination.
MT says the problem has been caused by some manx.net accounts holding weak passwords - something being exploited by outside companies to send large amounts of spam.
Users are now being asked to create secure and strong passwords, as many are likely to be unaware that their account has been compromised.
MT says incoming mail remains unaffected.
Weather postpones council's Easter fun day
Seven ferry crossings hit by water levels and dredging issues in Douglas
Sam Barks returns to Les Mis in transatlatic tour
DHSC commissioning rapid review of Noble's bed capacity
Progress being made on landmark's new building
Temporary traffic lights on TT course section
All government departments but one within budget
Unclaimed Manx lottery ticket worth £125,000 - is it you?!