Vodafone apologised after some customers using a BlackBerry handset lost emails in Europe, Middle East and Africa.
Vodafone, the world's second-largest mobile operator with 407 million customers globally, said the problem was due to a router error and said services were now being restored.
"We apologise to customers for any inconvenience caused and we will provide updates as necessary," the group said in a statement.
RIM, which has been hit before by high-profile outages in the last two years that affected millions of customers, said it was supporting Vodafone's efforts to resolve the issue.
Users on Twitter also reported problems with accessing emails on BlackBerries but it did not appear to be a widespread outage.
"Vodafone can confirm that some BlackBerry customers experienced issues with their data services this morning in Europe, Middle East and Africa," it said.
"Services are in the process of being restored and we continue to monitor the situation closely."