Fixity is a buzz word in today's digital world. ResCarta Toolkit has always created files with checksum validation for long term maintenance. At each step along the way the ResCarta Toolkit will generate a checksum. When the file has been added to your ResCarta archive it is ready to be validated by the Checksum Validation tool. This software tool will compare the original checksum to one it generates to see if any change has occurred since the time your digital object was created. It will notify you of any files where the checksums are not equal and allow you to replace the file from your alternate source. You did remember to create another copy of your archive, right? Remember lots of copies keeps stuff safe (LOCKS).