Back to My Mac: Some networks may not recognize some MobileMe members
Symptoms
In some cases, MobileMe members who have a period in the name portion of their member names will not be able to connect to their remote computers via Back to My Mac. This issue is specific to members who have a period in their member names, such as 1111.example@me.com.
Some Internet service providers (ISPs) are more strict than others in how they handle member names or "domain names". The Domain Name Service (DNS) translates domain names, such as www.apple.com, into numeric IP (Internet Protocol) addresses, such as 17.149.160.49. DNS allows computers to communicate with each other easily while still presenting Internet addresses in a manner that are easy for people to remember and use.
When Mac OS X initiates the transfers from your MobileMe account to your remote computer, some Internet service providers are interpreting the period in the username as a domain name separator. As a result, connections to Apple's Back to My Mac servers may not respond.
Products Affected
Mac OS X 10.5, Back to My Mac
Resolution
This issue is only specific to some Internet service providers, so affected members will only see it on specific networks. This issue usually will not persist when connecting to the Internet via a different ISP. In most cases, when you connect via a different ISP you should not see this issue.
If you do have a period in your member name, you should still be able to use Back to My Mac with your normal ISP as long as you use an alternate DNS provider. By default, your Internet Service Provider handles DNS services via their own DNS servers, however if there is a conflict with Back to My Mac, you may need to use an alternate DNS provider.
Open DNS provides alternate DNS services. You may wish to use their DNS servers or another alternate DNS provider. For more information about using Open DNS, including basic setup information, use Open DNS to change DNS settings.
Additional Information
Members who do not have periods in the name section of their account name should not be affected by this. If you have a member name that does not contain a period and you are still unable to connect to other computers via Back to My Mac, refer to Using and troubleshooting Back to My Mac in Mac OS X 10.5 instead.
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