If you created an iCloud account from an iOS 5 device or Mac running OS X Lion, but have other devices or computers that don't meet the system requirements, you may be able to use some features of iCloud with limited functionality. Please note that devices which do not meet the system requirements for iCloud are not supported by Apple or AppleCare for use with iCloud.
Mail
If you want to check your iCloud Mail, you can do so by visiting icloud.com from a Mac or PC (as long as it meets the browser requirements for icloud.com). Alternatively, you can configure a mail application that supports IMAP via SSL for use with iCloud Mail. More information is available here.
Calendars
If you want to check your iCloud Calendars, you can do so by visiting icloud.com from a Mac or PC (as long as it meets the browser requirements for icloud.com).
Contacts
If you want to check your iCloud Contacts, you can do so by visiting icloud.com from a Mac or PC (as long as it meets the browser system requirements for icloud.com).
Additional Information
* When moving from MobileMe to iCloud, if you have computers that do not meet the system requirements for iCloud, you may notice the following behaviors:
Mail may repeatedly give an alert message until you update your server settings for iCloud.
Syncing of Contacts, Calendars, Bookmarks, or other data types may fail silently, or may give generic alert messages.
iOS 3, iOS 4: You may receive an alert that your MobileMe account has expired.