I am running Excel 2010 and have been working on files and ONLY saving them to my USB memory stick.

On connecting the device to my PC (using an extension USB cord) I noticed a very brief minute blue like spark, and didn'y release until I tried to access my files that the entire content was wiped.

Painstakingly, I found some recovery software and was able to recover documents. Of all the Excel docs, all but 4 will re-open. Yes the ones I need. the message reads :

Excel cannot open the file 'LostFile_XLSX_608879.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.

Well I think it looks fine to me, and I endeavoureed to use the Open & Repair when openng the file too, with no luck.

Please can you help and tell me all is not lost.

Thanks

Hi,

What’s the version of Excel on the PC. This issue maybe occurs only when you send a workbook for review. The workbook file is saved as an Excel binary workbook. However, the workbook has an .xlsx extension that is appended to the file.

For detail, you can refer to the KB article:

http://support.microsoft.com/kb/928979

If the issue still persists, please let me know.

Best Regards,

Nick Wan

Well, this problem occurs when excel file gets corrupted or damage. In such case, When you try to open the .xls or .xlsx file, your whole document will not open properly and only characters displayed on the screen. For this, you should take the help of professional excel recovery tool. The tool is capable to repair corrupt excel file and recover the file in their original format.

I need help I have work due today. Twice I have lost my excel file.

I get the the Compatibility Report were it changed my excel workbook. Is there any way to recove my file with out having to redoe it all over again. Ihave Microsoft office 2010.

Hello Cwat,

Try to repair your file with 'open & repair'. It fixes all the problem when level of corruption is low. If you are unable to recover your data with this then try repair excel file program from 3rd party. 

Checkout these references would be help you:

http://social.technet.microsoft.com/Forums/en-CA/excel/thread/09d5bade-df9c-4253-9dcd-39b83a0b97f3

http://social.technet.microsoft.com/Forums/en-US/excel/thread/51bde1c2-ab35-4716-afa9-8e3207b2d7f5

Thanks

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