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You could try to go into your phone web browser options and in privacy settings clear your phone cache to free up some memory.
Also remove any unwanted media files such as photos, music and videosto free up memory space, by moving them onto your PC via USB mass storage mode.
Also as eKamran said, uninstalling some apps will also helps free up memory.
I hope these suggestions helped!
ive encountered this problem before..
let meask you some questions first
do you sync your mail to your phone? if yes then it could be one of the cause of your problem. because the data stored in the mail sync somehow is not deleted automatically butim not sure about this, it is only what i have observed on my phone
do you use social app? i yes it mayalso be acause of your problem as it is the same with the mail app it also uses the c: drive to save its files
hope this helps though im not 100% sure, when i stoped using this 2 apps my memory stoped decreasing
Hey I had no multimedia stored in phone memory, and only apps downloaded via betalabs were installed on phone memory.
Nonetheless, I did a "delete data and restore factory settings" and now I'm unable to install some critically important apps like Store client(I have tried both betalabs version as well as usual version available via http://go.store.ovi.mobi). I'm unable to install Nokia Drop, maps, wellness diary and all... but i'm still able to install apps via nokia suite/usb mode...
The progress bar of installation reaches 100% then says installation failed.
Also, I lost the nokia music app and all the preloaded apps like quick office/adobe reader after reset, how can I get them back??
I suggest that you reinstall your phone software using Nokia Suite.
Nokia N8-00 with Symbian Belle takes good care for C:/ Memory,
Saves about 100+ MB at first.
Its all the apps, Games and other instllation that Eats up the C:/ memory.
Best solution for this is to Use E:/ for all apps installation.
I had similar issues with my 808. Have a look here http://discussions.nokia.com/t5/Nseries-and-Symbia