If you are using standard logins to connect to SQL Server these items are lost when you save and deploy the package. You need to change the settings for the package security level. This can be done on the Properties for the package under Security | ProtectionLevel.
One option is to use DontSaveSenstive, setup a confiuration file and then set the login and password in the configuration file.
Another option is to try to change this to use Windows Authentication.
Regards
