25 February 2012 Last updated at 13:04 GMT
Apple has been forced to stop push email for iCloud and MobileMe users on iOS devices while they are in Germany.
However, the ability to receive emails by other means such as by opening the Mail app is unaffected.
Earlier this month a German court ruled that Apple's push technology infringed a Motorola Mobility patent.
Apple says it believes Motorola Mobility's patent are invalid and is appealing the decision.
This latest patent litigation only affects iOS devices. Apple's push service to desktop and laptop computers, and other services such as Microsoft Exchange ActiveSync are not effected.
Apple has published a support note on its website detailing a workaround for customers that are affected by the decision.
Patent battles
Apple and Motorola Mobility have been involved in a series of patent disputes in recent weeks.
In December, Apple briefly pulled several iPad and iPhone models from its German online store after Motorola Mobility enforced a patent injunction against the company.
More recently, Apple won a separate patent dispute with Motorola over the "slide to unlock" feature on many smart phones.
Google announced last year that it plans to acquire Motorola Mobility, which holds 24,500 patents, in a $12.5bn (£7.9bn) deal.
