SharePoint Farm Passphrases and Configuration Cache

While adding a server to a client’s farm we discovered that they had lost track of their farm passphrase.

What now?

No biggie, Set-SPPassPhrase to the rescue, right?

I threw down one of these and expected I’d be good to go:

$passphrase = ConvertTo-SecureString -string "y0L0$wag" -asPlainText -Force
Set-SPPassPhrase -PassPhrase $passphrase

When it came time to add the new server to the farm, I got one of these for my trouble:

Failed to connect to the configuration database.

An exception of type System.ArgumentException was thrown. Additional exception information: Error during decryption. Ensure the passphrase is correct.

I knew the passphrase was correct, you don’t forget a passphrase like y0L0$wag (like y0L0$wag, not actually y0L0$wag but equally memorable).

The culprit: cache.

Clear your configuration cache

I adapted this Clear-SPConfigCache script to flush the configuration cache on all core SharePoint Servers. You don’t need to worry about SQL, SharePoint Add-In hosts or Office Online Servers. Once complete, I was back on my merry way, adding servers left, right and centre.