Can i change battery on Samsung 4 without losing everything on my phone

If you have a Samsung account associated with your phone you can log in here (https://account.samsung.com).
You then select Find My Mobile and click on unlock my device. Once you are in your phone you can change your password again.

Depends on the type of phone there might be away to unlock it. If u have a online account were u can lock and locate it. There might be a function of to change the password online. Call customer service. if you don't mine losing everything on your phone. There's most likely be a reset button on the phone, which will reset your phone to default. Common places would be on the side for phone without access to battery. Or under the battery compartment. It would be a small hole just big enough to insert a paper clip. Check your owners manual for it location. Tip. If u r forgetful. Try having a lock file on file with your passwords.

If you forgot your phone code, what you can do is to have a hard reset. Hard reset means restoring the phone back to its original factory settings. if you do not do a factory reset, then you cannot change the code. It is the only way that you can change it. But on the other hand, this method deletes everything that you have saved in your phone memory. Including images, contacts, videos and everything on your phone memory. To do a hard reset on your Samsung GT-C6712, do the following steps:
1. Turn on your phone.
2. Open your dialer/dial pad.
3. Type: *2767*3855#
4. If there will be a confirmation message, just choose Yes.
5. Wait for the process to finish.
Note Use the code on your own Risk
you will lose all the contacts and private data
Note: After the hard reset, your phone will automatically reboot itself. If your device freezes after doing a hard reset, just do this:

Hi,

Click on the link provided for the official Samsung downloads: Samsung Official Downloads.

The service is free from Samsung.

All the best

ben

To Unfreeze the Samsung Champ model Phone get the Unfreeze Code at
Unlocking4u.com

Go to the following site and download the manual.

http://www.samsung.com/us/support/downloads/SAMSUNG%20S860

The manual explains everything you want to know.

How To Unlock Samsung A177 1. Turn on your Samsung mobile phone without the SIM card in.
2. Type #7465625*638*
3. Now enter your 8-digit unlock code
4. Type #
5. If worked, phone should say “Network Lock Deactivated”
6. Your Samsung phone may automatically reboot at this point.
Once you finish the above instructions you should have yourself a completely unlocked Samsung A177. Enjoy!

try this code *2767*3855# no phone data will lose

Back up any saved music/sms/contacts/pictures/videos onto a pc
(you shouldnt lose them but just incase)

1. Phone Settings.
2. Security
3. Code is the last four digits of your phone number (unless you have changed it personally)
4. reset settings