I've been struggling with this error for a few weeks now. Only recently we retracted the MacroView DMF solution and suddenly we were able to create sites again. I had to re-deploy the solution so that users can continue to save emails into SharePoint. Unfortunately, that also reintroduces the issue with creating new sites.

We have been able to create Blank Sites and Document Center sites only. ALL other templates give the error message in the subject.

Here's a small snippet from the logs:

Detected use of SPRequest for previously closed SPWeb object. Plea
se close SPWeb objects when you are done with all objects obtained
from them, but not before. Stack trace: at MacroView.DMF.Cache.
WebAddReceiver.

And more:

Error adding Cache Job on activation : System.UnauthorizedAccessExc
eption: <nativehr>0x80070005</nativehr><nativestack></nativestack>
at Microsoft.SharePoint.Library.SPRequest.RegisterEventReceiver