SCUP 2011 and File Digest errors

This one has been bugging be for quite some time...

Sometimes, when you've published an update from SCUP to WSUS as metadata only, it fails to publish the full content later and gives an error of "incorrect file digest".

What's going on here?

This is where the publisher has created an updated binary for the same release, but not updated the Origin File Digest in the metadata.

When SCUP imports a update, it stores a SHA-1 Base64 hash of the file which is held in the SCUP database. When you go to publish "full content", it compares the hash of the downloaded file with that in the database. When the don't match, you get the file digest error.

Ultimately, this is a mistake on the part of the vendor, but they're pretty inconsistent at fixing them (Dell being a particular offender).

So how do we fix it to get that critical update out?

1. Download the binary directly from the vendor
2. Get the SHA-1 Base64 encoded of the file (I used online-convert.com)
3. Take a copy of the SCUP sdf database file for safety 
4. Open the SCUP sdf with CompactView
5. Query the installableitems table to find your problem update 
6. Update the FileDigest value in the SCUP database with the new value
7. Run SCUP and you'll be able to publish the full content.

An alternative to steps 1 and 2 is available if you already have the SHA-1 in another format. For example, Dell updates provide the SHA-1 hash in hex format on their website so convert that into Base64 using something like this.

Step 2 can also be done using any checksum calculator, e.g. MS Checksum Validator, but you'll still need to convert the hex format into Base64

Enjoy!