Before updating Firefox, try closing or disabling such programs; for example, Spybot Tea Timer and Logitech Quick Cam software have been known to interfere with Firefox updates.
SPARQL contains capabilities for querying required and optional graph patterns along with their conjunctions and disjunctions.
SPARQL also supports aggregation, subqueries, negation, creating values by expressions, extensible value testing, and constraining queries by source RDF graph.
The results of SPARQL queries can be result sets or RDF graphs.
A whole set of different ways to use the find And Modify command.
The first find And Modify command modifies a document and returns the modified document back.
The second find And Modify command removes the document.
The second find And Modify command upserts a document and returns the new document.
It's possible that another running program or a previous instance of Firefox that did not close properly is interfering with the Firefox update process.
This error can also occur if you share your computer with other users, and another user's account is still logged in with Firefox running.