HTC One E8 - Manual (Page 110)

You cannot undo encryption on the phone storage. If you want to return to an
unencrypted phone, you must perform a factory reset.
Once you enable storage card encryption, only new files added after encryption will
be encrypted. Files already on the card will not be encrypted. Also, storage card
encryption doesn't reformat or erase your card. Encrypted files on the storage card
can only be opened by the phone that encrypted them.
How to encrypt
1. Go to Settings, and then tap Storage.
2. Tap Phone storage encryption. Or, tap Encrypt SD card content.
3. Tap Next.
4. Enter the lock screen PIN or password, and tap Next.
5. Tap Enable encryption.
During phone storage encryption, the phone may restart a few times. When storage
encryption is complete, enter your PIN or password.
If you turn off SD card encryption to stop encrypting new files, previously
encrypted files will remain encrypted. To access these files, you must enable
encryption again for your storage card.
Google Drive
Using Google Drive on HTC One (E8)
Store your photos, documents, and other files on Google Drive to access them on
HTC One (E8), your computer, and your other mobile devices.
On HTC One (E8), just use your Google Account to sign in to your Google Drive
storage. You can then:
§ Use Gallery to upload your captured photos to Google Drive.
§ Share a link to your Google Drive files by email.
§ View and edit Office documents that are stored in Google Drive. After creating
new Office documents, you can also save them to Google Drive.
§ View PDFs that are stored in Google Drive. You can also export Office
documents as PDFs to Google Drive.
§ Check your available Google Drive storage space in Settings.
§ Back up HTC One (E8) to Google Drive, so you can easily restore your backup
to another HTC phone next time.
§ Use the Google Drive app to manage your online storage.
110 Storage