If you use GoToMyPC, you will need to reset your password.

A hacker may have gained access to the GoToMyPC server and stolen user passwords and names.

BGTMPC has sent out a message to all users that they have reset passwords:

IMPORTANT SECURITY MESSAGE FROM THE GoToMYPC TEAM

Dear Valued Customer,

Unfortunately, the GoToMYPC service has been targeted by a very sophisticated password attack. To protect you, the security team recommended that we reset all customer passwords immediately.

Effective immediately, you will be required to reset your GoToMYPC password before you can login again.
To reset your password please use your regular GoToMYPC login link.

Recommendations for a strong password:

Don’t use a word from the dictionary
Select strong passwords that can't easily be guessed with 8 or more characters
Make it Complex – Randomly add capital letters, punctuation or symbols
Substitute numbers for letters that look similar (for example, substitute “0” for “o” or “3” for “E”.

They neglected to urge users to make sure they do not use the same passwords on multiple websites. So it is also advised to change any passwords being used on other websites.

GoToMyPC has not been forthcoming as to what exactly was breached, whether it was stolen user names and passwords or that someone stole credentials from a different website and found the same user name and password being used on GoToMyPC.

Source: Graham Cluley