Backup Awareness Month is usually in June, but I think Apple and Microsoft must have decided to move it to October.

Both companies are giving users spectactular reminders of why you must regularly backup important files.

Microsoft's getting most of the attention for the glitch that lost contacts and other files stored online by users of the Sidekick mobile phone, which its Danger unit developed and powered for T-Mobile USA. It began with an outage last week and is still being analyzed by the companies.

Microsoft should check and see if its $500 million purchase of Danger -- which closed in April 2008 -- is still under warranty.

Meanwhile, Apple acknowledged Tuesday that some people who upgraded their Macs to Snow Leopard, then logged into "guest" accounts they had created earlier on their computers, had their personal files erased.

Apple told InformationWeek the company is "aware of the issue that occurs in extremely rare cases, and we are working on a fix" but didn't specify when it will be ready.

From the story:

According to Apple discussion forums, the problem is related to a change in the way Snow Leopard handles guest accounts. Users who upgrade from Leopard to Snow Leopard with guest account enabled have found that opening the guest account in Leopard can destroy personal data.

I wonder which glitch erased more files. Either way, it's time to save your stuff somewhere safe.