A facility for managing a document conversion environment is described. In various embodiments, the facility includes a native application associated with a native document type and an isolation service. The isolation service determines whether a native application associated with the native document type has started and when it has not started, starts the native application and causes the started native application to load and convert a native document to a common document format, wherein the isolation service starts a single instance of the native application and monitors the single instance of the native application so that it complies with specified a parameter, condition, or setting of operation.