Microsoft on Tuesday added the option to encrypt Hotmail sessions at all times, not just during the sign-in process. SkyDrive, Photos, Docs, and Devices, meanwhile, will automatically be encrypted going forward.

At this point, Hotmail only uses this encryption process, known as HTTPS, during the sign-in process in order to protect your password. HTTPS keeps e-mail encrypted as it travels between your Web browser and servers and is mostly used for things like banks and credit card company Web sites.

Now, Microsoft will allow users to enable HTTPS at all time for Hotmail inbox, calendar, and contacts.

"By using a connection with advanced security features, you can be even more confident that your account is safer from hijackers, and your private information is less likely to fall into someone else's hands," Dick Craddock, group program manager for Windows Live Hotmail, wrote in a blog post.

To enable, go to account.live.com/ManageSSL. "Once you enable this feature, all of your future connections to Hotmail will be delivered over SSL," Craddock wrote. With it turned on, however, some connections won't be available, including Outlook Hotmail Connector, Windows Live Mail, and the Windows Live app for Windows Mobile version 6.5 and earlier and Symbian.

The move comes several days after security think tank Digital Society gave Hotmail a D- on its security report card, while Twitter and Facebook failed. Google's Gmail received an A on that report, likely because of its existing HTTPS efforts.

In January, Google made Gmail HTTPS an opt-out feature; about two years after it made the encryption technique opt-in.