Help me - Excel cannot open the file '(filename)'.xlsx'

Hi Experts,

i have big problem with my file. My xlsx file which shows an error "Excel cannot open the file 'file name 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."

i also used this software, but not work
- Repair my excel
- Kernel data recovery
- Recover Excel File
- Excel Recovery Tools

File open - OK
OLE Header Corrupt - X
OLE Header Structure Corrupt - X
Reading BIFF - OK

Is there any person to fix it?
Help me Please
This my important file

Firstly, nobody will be allowed to accept a payment, so please don't offer it.

Secondly, please check that the file in question has not suddenly developed a double suffix (e.g.filename.xls.xlsx).

If you attach the file here, someone may be able to recover it for you.

The lesson here, as if I really need to tell you, is that you should NEVER have just one copy of an important file: you should be maintaining regular back-ups and making incremental copies each time you work on the file.

Unfortunately the attachment icon doesn't work at the moment, so to attach an Excel file you have to do the following: just before posting, scroll down to Go Advanced and then scroll down to Manage Attachments. Now follow the instructions at the top of that screen.

Hi AliGW,
This my corrupt file. Hope you can help me. Very thank you

If I change its extension from .xlsx to .xls, I can open it, but the file is completely empty. I think you are out of luck. Time to rebuild the file. When you do, start making incremental copies each time you make any major amendments, and back it up regularly.