Forum Discussion
b26080 - ISSUE - ADPrep for Windows Server 2025 schema fails due signature: error 0x800b010
If you check your ldif.log file, you will find the root cause of your issue. Error says: Failed to verify file signature: error 0x800b0109.
This is related to the signature on the schupgrade.cat file next to adprep.exe tool. Root CA (Microsoft Development Root Certificate Authority 2014) in that chain is not trusted on your server. If you go through the properties and find the root cert, you can install it in local “Trusted Root Certification Authorities” store, the error goes away - at least it did for me.
Since I was not the only one that stumbled upon this, I decided to write short blog post about it. You can get more info including the base-64 cer for the root CA here: Windows Server 2025 (26080) – ADPrep error 0x800b010a
If you check your ldif.log file, you will find the root cause of your issue. Error says: Failed to verify file signature: error 0x800b0109.
This is related to the signature on the schupgrade.cat file next to adprep.exe tool. Root CA (Microsoft Development Root Certificate Authority 2014) in that chain is not trusted on your server. If you go through the properties and find the root cert, you can install it in local “Trusted Root Certification Authorities” store, the error goes away - at least it did for me.
Since I was not the only one that stumbled upon this, I decided to write short blog post about it. You can get more info including the base-64 cer for the root CA here: Windows Server 2025 (26080) – ADPrep error 0x800b010a
Wonderful catch Joze_Markic. Appreciate your blogpost on this! Hope that the Microsoft Server team is aware about this regression and can fix it before release.
