Boxcryptor

With premium features, Boxcryptor shines. Encrypt files loaded to the cloud, as well as files on your computers and thumb drives. Boxcryptor has phone apps, but the bonus is that if you're like me and have multiple cloud providers, Boxcryptor unifies them under one app. Share files just as you would with OneDrive or Box, but know that the original file is safely encrypted against prying eyes and hackers. Highly recommended!!!

Please ad support for encrypt the existing files in onedrive and encrypt the entire folder instead of encrypting one file at a time.

I use Boxcryptor on a 1st gen Surface RT. It runs well, if a little sluggish. I have not experienced any sync issues, and in general feel it works as well as the Android equivalent. Keep up the good work!

I installed the App for Windows 10 from the store, but it did not create it's virtual drive, so it was unable to encrypt anything.

I hate this app with all my heart... I tried to backup my gazillion, completely useful files from my Downloads and encrypt them with Boxcryptor. The files, in total, were probably around oh, let's say, 3 GIGABYTES!!!!!!!!!!!!!!!!!!!!!! Anyways, after I backed them up, I realized I didn't really want them on there anymore so I decided to remove the files from my Boxcryptor. THEN WHAT DOES IT DO, you ask?? It completely erases the files and wipes them away from my hard drive.... Even after using tons and tons AND TONS of hours and programs and external drives trying to retrieve the dumb files, I COULDN'T FIND THEM!!! So, all I say to you is that, if you want your entire file system to be accidentally wiped, you should definitely install this app!! :)