Python xlwt create faulty excel book

Question

I am trying to use xlwt to create a output file (in .xlsx format) with multiple tabs. The version number of my Python is 2.7, and I am using Aptana Studio 3 as IDE.

I've used the xlwt package before, with the same environment, to carry out the same task. It worked well. But this time, it works well at first, then suddenly, the output file became faulty that cannot be opened by MS Excel.

Here is a clue that might be helpful. My Aptana Studio 3 decide to open .xlsx in its own editor rather than start MS Excel. Although this happens before the problem, I am wondering if it is related.

The file looks normal when it is opened in Aptana3, but when I closed it, and open it with MS Excel, an error pops up:"Excel cannot open the file "output.xlsx" because the file format or file extension is not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file."

May I know how I can get over this? Any suggestions are welcome. Thanks.

Answer 1

The xlwt module cannot create .xlsx files. It is a writer for .xls files.

The warning is due to a feature in newer versions of Excel called "extension hardening" which means that the file extension has to match the file type.

If you change the output file extension in your program to .xls the warning should go away and Excel will read the file.