Magento stores passwords in the admin_user table in the salted MD5 format. In the unusual case that you are unable to access your store and the forgotten password, the link is not working, you can update the Magento admin password by editing this hash directly.
3.The left side is the hash for your password while the right side of the colon is the salt. Since cracking this is not very likely for you, we want to use own md5. To do this, use a tool that will convert your password/string to md5 such as this site or similar tools. – https://md5.my-addr.com/md5_salted_hash-md5_salt_hash_generator_tool.php
4. In your tool of choice generate the password hash either with the same salt from the admin_user table or generate a new one.
5. Insert or copy the new hash with salt into the password field in the same format with the password hash on the left and the salt on the right of the colon.
6. Test your new login and it should now let you into your admin.