"We've seen some issues with using Hotmail on the new Apple iPad," acknowledged Mike Schackwitz, the Hotmail program manager, on the 'Inside Windows Live' blog.
"Specifically, composing and replying to an email is not working for some of our users."
iPad users have reported problems with Microsoft's web-based email service, including the iPad's Safari browser freezing and an inability to compose new messages or reply to received mail.
"I can read mail but I can't compose a new message or reply to a message," said someone identified as 'mitchgrrt' on Apple's support forum on April 6, just three days after the tablet went on sale in the US.
"iPad won't let me type in the message input area, and Safari hangs."
"We're working with Apple to understand the issues, and we'll fix them as quickly as possible," said Schackwitz. He did not provide a timetable for a Hotmail fix.
On Apple's support forum, most iPad users said that they were able to grab their Hotmail messages after setting up the tablet's baked-in mail client to access Microsoft's service as a POP account.
Others urged iPad users who were experiencing problems to switch to the mobile Hotmail site, which uses a stripped-down interface more suitable for the smaller screens on smartphones.
Microsoft has since redirected all iPad traffic to the mobile version.
This week, Microsoft revealed it would begin rolling out the latest enhancements to its Hotmail webmail service, with an aim to reduce clutter and make it easier to send photos and handle Office documents.
See also: iPad unlikely to be a hit in the UK