Hi I have same issues with 2013 with running a macro from a large workbook which imports data files one by one, calculates out and pastes the output onto a front sheet row by row then saves the new data with trading signals as a CSV file and closes it before going to the next. Takes 10 times as long as 2010, looks like it's semi crashed, pastes the data but doesn't save any CSV files. Before I downgrade (and pull what little hair I have left out!)interested to see any other postings Bukovnik's query raises. Thanks