Why my phone storage taking more space in 720?

[WPCentral Question]

I am using Lumia 720 preview for developers version. I have all apps installed in SD card. If i do storage check in my phone in others column 1.7GB occupied. How to remove those files. when connected to PC nothing showing. In storage check system OS memory is 1.9GB but in Storage sense it shows 3.1GB. Why this difference and how to erase memoery occupied in others.

 

[anon(8098745)]

The "Others" includes "everything else" (the "other" stuff) on your phone that doesn't belong to the known storage categories. Files in the "other" category are usually created by apps and services on the phone and cannot be deleted by the user. Some examples of "other" files include the database for your phone contacts and the files temporarily storing the latest from your social network newsfeeds. Here's the basic formula we use to calculate it:
total storage capacity – size of storage categories – free storage space = "other"
If you want to erase the content of Others in SD card then format the SD card.(Backup your stuff before formatting).
Format the Card by connecting it to PC.
If u want to get rid of "Others" present in the internal memory then do a hard reset.
Caution: Hard reset will erase everything that is present on your phone i.e: apps,images,music,contacts,etc.
If u want to do hard reset then enable backup in your phone(sms and app list) and then only proceed with hard reset. After the hard reset add you Microsoft account and all other account linked to your phone and sync them.
Note: all the apps will have to be downloaded again.