[ovirt-users] Cannot set storage domain on maintenance

Hi, We're running ovirt-engine-4.1.5.2-1 and we're trying to set one of the storage domains on maintenance in order to remove it, as there's nothing left on it besides some templates. To do so, I open the 'Data Centers' tab, then the 'Storage' subtab, select the storage domain and click on 'Maintenance'. When asked for confirmation I click OK. After that, this error message is shown: Error while executing action: Cannot deactivate Storage while there are running tasks on this Storage. -Please wait until tasks will finish and try again. As far as I know, there are no pending tasks on this storage. The Events tab only shows a movement of a disk which has nothing to do with this storage domain. What can I do to solve this? Thanks. Nicolás