In order to edit workbooks in this {0:DocumentLibrary} they must first be checked out. To edit this workbook, check out the ...

In order to edit workbooks in this {0:DocumentLibrary} they must first be checked out. To edit this workbook, check out the workbook in the {0:DocumentLibrary} to the server (not to your local drafts folder) and then try to edit it in {0:ExcelCalculationServer} again.