I recently had an issue while trying to configure the authentication provider for a SharePoint 2007 site. Regardless of the authentication provider that I selected, clicking the save button would result in the following error:
An object of the type Microsoft.SharePoint.Administration.SPWebApplicationProvisioningJobDefinition named "Provisioning 1aa06c49-f543-41c2-b3f6-ce7884a9b71d" already exists under the parent Microsoft.SharePoint.Administration.SPWebService named "". Rename your object or delete the existing object.
After coming up short on answers from multiple Google searches, I dug into the Timer job Status page under the Operations tab of Central Administration and noticed that for every attempt I made to configure authentication for a site that there were two jobs being created. One job would pass while the other would fail. Previously unknown by me, the SharePoint site had been configured in a Server Farm configuration, so the two jobs that I saw coincided with the two servers in the farm (the job had to be provisioned to each server in the farm). After a quick investigation, it was determined that the two servers were running different versions because a hot fix had been applied to one, but not the other.
In my situation, this was a new SharePoint install and, not being familiar with configuring SharePoint in a server farm, I was able to temporarily remove the second server from the farm and move forward without any errors. The real test, however, would be to apply the patch to the second server and go through the process again.
There were other constraints, beyond the scope of this post, that made temporarily removing the second server more ideal than simply applying the patch to see where it got me. I will update this blog when I have added the second server back into the equation.