Can't create backup media for 1 job

[Tgh_TMCentral]

I'm backing up 3 Server 2012 R2 instances with Agent for Windows. All have same AV and are basic setups. One backup is completing with a warning when trying to backup the recovery media: This access control list is not in canonical form and therefore cannot be modified. This causes me to be unable to create recovery media. Any ideas? I've run icacls C:\Windows /verify /t and C:\Program Files /verify /t and corrected one folder that it found with the issue, but it did not solve the problem... Any ideas?

Support case: 03829798

Relevant log entries:
[23.10.2019 22:53:34] <01> Info Backing up recovery media files
[23.10.2019 22:53:35] <01> Error Failed to add recovery media files to storage
[23.10.2019 22:53:35] <01> Error This access control list is not in canonical form and therefore cannot be modified. (System.InvalidOperationException)
[23.10.2019 22:53:35] <01> Error at System.Security.AccessControl.CommonAcl.ThrowIfNotCanonical()

[Egor Yakovlev]

Hi Patrick.

I can see your case been picked up and support has offered a remote session in 5 hours from now.
Not to ruin their work with my guesses on how to fix that error, please follow up that thread after the session with Veeam support engineer - I am 100% positive that she will fix your issue.

/Cheers!