On my phone phone memory automatically goes low day by day, even ifi do not install applicatios on phone memory. I have checked phone memory details and approx. 112 MB other files.... What are those other files and how to delete them?
Welcome to the Nokia forum.
The 112MB you're mentioning is caused by usage of the phone, which results in a 'memory full' pop up. I had the same problem with my own E72 and this can be fixed really quickly with a hard reset.
Make sure you make a back up with Nokia Suite first by going to Tools > Back up. Don't tick the Settings box as this will backup the bug that's causing this. Once you've made the backup, enter *#7370# into your phone and default security code 12345, unless you've changed this code yourself.
When the phone has rebooted, reconnect it to Nokia Suite and update or reinstall the current software to make sure you really get rid of all possible bugs. You can do this by clicking on the green arrow in Nokia Suite.
After you've done the above, place the backup back onto your phone by going to Tools > Restore in Nokia Suite and the phone will work perfectly again.
Let me know if the memory full message still pops up. You will also notice that the phone will work a lot faster once you've done a hard reset, so definitely give it a go and let me know how you get on!