How i delete my unsaved Phone Nos? Inbox>text message > send message>contact look up? more? unsaved No> how i delete that one

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Go to the saved message then highlight it and choose the delete option.

Most feature phones have a very limited amount of memory on them, usually between 100-250 text messages are allowed. This means you will have to go through and delete some of your messages in your inbox. You can delete unwanted messages one by one or delete the entire inbox. The delete buttons exist in different places depending on your cell phone model.

Simple solution. Delete your old messages in outbox and inbox. If still won't let you receive or send text contact your service provider.

try to go to garbage can and delte all the deleted messages

first try contacting your provider and have your line checked,,

if it dont work, try resetting your phone, but please backup all your neede files because resetting the unit wipes all data off,

try asking around for the smsc1 center number for your current provider an enter it to the sms settings for smsc1 found in the sms setting menu of your phone

Try this link
thisisfordevices.blogspot.com/search/label/Nokia%206300

Take a picture and select it to send. Under Options on the camera screen, it will populate the screen to send. if you go to your recent list (last option), it will bring up folks you've TEXT. Select the names you want to remove, then Options. You can delete the contacts here, which removes them from your recent list, but not your "hard contact" list in the main phone.

am unable to send SMS messages? As a set limitation to the phone's design, if the SMS Inbox is consumed, the phone's alternative is to send as an MMS.
If a customer is calling and their phone is sending SMS messages as MMS messages, please advise them that they may have an excessive amount of SMS messages in their inbox. Advise them that deleting some or all of these messages should correct the problem.
To delete messages:

1. Press Menu
2. Scroll to and Select Messaging
3. Press Options
4. Scroll to and Select Cleanup Messages
5. Scroll to and Select All, or Inbox
6. Press Yes, to Delete Messages
   
   

have you tried a hard reset? remove the battery, let it sit for a minute and start it up again.