If you are using SQL authentication for the database connections in your SSIS package you may get the following error message when you schedule your SSIS package.
Description: Failed to decrypt protected XML node "DTS:Password" with error 0x8009000B "Key not valid for use in specified state.". You may not be authorized to access this information. This error occurs when there is a cryptographic error. Verify that the correct key is available.
You can do the followings to fix the problem:
1. 1. Change the Package Security ProtectionLevel from EncryptSensitiveWithUserKey to DontSaveSensitive
2. 2. Enable package configurations by right click on the package design surface and click "Package Configurations.." to start Package Configuration Organizer.
3. Create configuration file using the Package Configuration Organizer.
4. 4. Modify the configuration file and store the password information of your connection string in the configuration file
5. 5. Run your package using the configuration file.