How can i clear the phone memory.there is no media, no cache, nothing installed in it;Nokia 5230

It is possible that the phone has hung up becausethere are errors in the software. So to reset remove the battery and the memorycard from the phone. Using your PC , scan the memory card for any corrupt filesor media files with virus- it is possible when they are downloaded from unsafesites. If so remove or format the card. Copy only valid files to the card anddo a scan before it is replaced. Now replace the card and battery and switch onthe phone. If the phone hangs up or is slow when it is switched ON , then it ispossible that the fault is relative tothe software and will need a reinstallation. Possible hardware issue cannot beruled out. Seeking help from the authorized service /supportcentre is most ideal. Take estimate and decide.

try to update your software of your mobile.

You might need to format the phone as it is possible that some corrupt programs have filled up the memory. Also try to reset the phone for errors in the software. So to reset remove the battery and the memory card from the phone. Using your PC , scan the memory card for any corrupt files or media files with virus- it is possible when they are downloaded from unsafe sites. If so remove or format the card. Now replace the card and battery and switch on the phone. If the phone hangs up then it is confirmed that the software is corrupt and will need a reinstallation. Seeking help from the authorized service /support centre is most ideal. Take estimate and decide.
http://www.blogsdna.com/2278/how-to-format-nokia-n72-n73-n81-n95-nseries-mobile-phones.htm

you might want to check your java scripts, also try master reset see link below --> discussions.europe.nokia.com/.../Nokia-Nuron-5230-how-to-master-reset/m-p/773627

check first if the phone memory is indeed full, it should be under settings then phone. also check if the default memory being used is your phone, if you have a memory card change it to memory card. if your phone memory is full you just need to delete files you don't need. you don't have to reset your phone.

dial *#7370# then your security code

sir, you have to format your entire phone memory , for this do the following 1. Switch off your phone...
2. Remove SIM card & memory chip...
3. Now press & hold keys - 3,*,call green) ...
4. Then without leaving these three buttons press power button...
5. Formatting task will be started...
6. Remember its a very rare trick....

If you use the internet on your phone regularly, clear the browsers cache and history, especially if you use Opera Mobile. I was surprised to find that Opera Mobile on my Nokia 5230 was hording about 10MB of phone memory for the cache.

Also, only install critical apps to the phone memory, the rest should be installed to a memory card as little by little the used space all adds up.

just go the technician,,,ask them what is the real problem of your cellphone