Disclosed is a 
system and method that uses 
digital signature technology to authenticate the contents of one or more manifests located on a storage device. Each manifest contains a 
list of file records, where each 
record contains the name of a file stored on the storage device, and a signature value derived from the contents of the file. At boot time, the gaming 
machine first authenticates the contents of the manifest and then authenticates the contents of the files using the signature value stored in the manifest. Files are verified using the signature, as they are needed, during the boot up of the 
operating system and throughout normal operation. This method reduces the boot time of the gaming 
machine and eliminates the need to check digital signatures for each individual file or over the entire contents of a non-secure media. Similarly, a method of adding 
authentication ability to legacy 
software components without necessarily altering the legacy 
software components is disclosed. Introduction of a stronger 
authentication algorithm, or when a private key has been compromised would normally require the 
software component to be re-built to support the new 
algorithm or private / public key pair; however, a method is disclosed where algorithms and key pairs may be changed and applied to legacy software without having to re-built, re-test, re-sign, or re-submit the component to regulatory agencies for approval. Also disclosed is a 
system and method of establishing a trusted environment containing a gaming 
operating system and associated 
authentication module, 
file system drivers, and / or network drivers that may be used to in the process of authenticating contents of one or more manifests located on a storage device.