By Paul Pruitt - MCP, CompTIA A+,
CompTIA Net+, HDI Helpdesk Analyst

Preliminary Considerations

1. You would be well advised to take a look at Microsoft's articles on the subject first. If you have Excel 2002 and 2003, see the MS Office Assistant Article about recovering files:
   http://office.microsoft.com/assistance/preview.aspx?AssetID=HA010346561033&CTT=6&Origin=EC010553071033.
   
   
2. The Microsoft Knowledge Base Articles (more advanced) are here including Excel 97 and 2000 articles.
   1. For all of Microsoft's Excel 97official methods, including the complicated external file reference method is available here:
   http://support.microsoft.com/default.aspx'scid=KB;en-us;Q142117.
   2. For all the Excel 2000 methods look here:
      http://support.microsoft.com/default.aspx'scid=KB;en-us;Q179871.
   3.  For all the Excel 2002 and 2003 methods look here: http://support.microsoft.com/default.aspx'scid=KB;en-us;Q291057.
      
      
3. This newsgroup post looks good too: http://preview.tinyurl.com/23zdbb.

Warning: Always work from a copy of your file so you don't make things worse!  See step 7. if you can't make a copy of the file.

1. Close down Excel, reopen it and try to open the file again.

2. If this doesn't work, restart the computer, open up Excel and try to open the file again.

3. If this doesn't work, delete the contents of your c:\ Windows\temp directory then reboot. Try again.

4. If this doesn't work, open Excel in Safe Mode. This will disable VBA and Add-ins. Click on Start then Run then enter (including the quotes and the /s extension): "C:\Program Files\Microsoft Office\Office\excel.exe" /s ["C:\Program Files\Microsoft Office\Office10\excel.exe" /s (for Excel 2002, Office XP, click cancel if the MS Office Installer starts, Excel in safe mode will still start)].Try to open the file.

5. If this doesn't work, be sure to scan the file for viruses. Make sure your macro heuristics scanning option is turned on. Ask your IT administrator how to do this.

6. If you don't find a virus, try to open the file in Word.  Note after you do this, you will probably have to make another copy because Word sometimes destroys the binary structure of Excel (I think).

7. If this doesn't work, try to determine if the file is unrecoverable on the disk. Open the file in Explorer and try to copy it to another location.  I know  I told you to to  work from a copy of the file so you have already done this.  I apologize, the steps were written at different times. If you can copy the file to another location skip to step 9, if not the actual sectors on the disk may be corrupted. If the data is valuable enough to you, there are several labs that can recover files off damaged disks, you can find a lab here: http://www.disasterrecoverygroup.com/ (there are other such services too). Damaged hard disk file recovery is not easy to do on your own. If you would like to try there are some free tools here: http://www.s2services.com/diskimagingfreeware.htm.  Try Roadkil's Unstoppable Copier and recoverdm. There are several programs you can buy too, one for as little as 40$. A good list is here: http://www.snapfiles.com/
   shareware/system/swdatarecovery.html. Bad floppy recovery is easier though just like damaged hard disk recovery often doesn't work. An excellent free Windows based program for floppies can be found at: http://www.simtel.net/pub/pd/60018.html.

8. Try to open any damaged disk recovered file immediately, miracles do happen.

9. If the recovered file won't open or you could copy the file to another location, try to open the file in a more recent version of Excel. As the version numbers increase, their ability to recover corrupt files increases. If this doesn't work or such a version of Excel is not available, see if some other spreadsheet application is and try to open the file in that program.
   
   A hopefully exhaustive list of spreadsheets is here: http://en.wikipedia.org/wiki/List_of_spreadsheets.  Most of the spreadsheets here will have filters to allow the opening of Excel files.  Most commercial spreadsheets will have a fully functional trial version.

10. If Microsoft can't help you and you've exhausted all the free methods above for damaged disk recovered or copy-able files there are a number of excellent commercial applications which will recover your files almost immediately. I have used most of the programs in the list and frankly don't like to say anything bad about any of them because somebody is making a living from them. However as they say in this business "Try before your buy!" Always try the free demos first.
    
    Broadly speaking Excel Workbook Rebuilder, RecoverMyFiles, XLS Regenerator and FinalData Premium are more labor intensive and don't have the intuitive turnkey features.

    The others four may do roughly equivalent jobs, although EasyRecovery File Repair at $299 is an investment for future corrupt documents of the Word, Access, PowerPoint, Outlook and Zip variety as it will recover all these if you need it.

    ExcelFix and ExcelRecovery are solid. Advanced Excel Repair, Stellar Excel Recovery, R-Excel, Kernal Excel Recovery and Repair My Excel are newish but appear professional and are lower priced than the pioneers made by Cimaware (ExcelFix), Recoveronix (ExcelRecovery) and Ontrack (Easy Recovery File Repair).

    1. Corrupt xlsx2csv - a new freeware GUI program for recovering the data from corrupt Excel 2007 files...If corruptxlsx2csv doesn't work, you have Excel 97-2003 files or you need format recovery try ExcelFix demo first.

    2. I believe my sponsor ExcelFIX is the best. A demo is available which will show your all of the recoverable information. For $129 you can recover data, formulas, formats, charts and more. It's available here: http://www.cimaware.com/info.

3. Another excellent program, is ExcelRecovery. It also cost $149 (with a $30 discount available if you link to their site) and recovers formatting. The Demo version allows you to save 300 cells whereas ExcelFIX only displays them. The company that makes the product Recoveronix along with Ontrack and ExcelFix' Cimaware are the big names in corrupt file recovery. It is available here: http://www.officerecovery.com/.

4. Advanced Excel Repair (AER) - supports batch recovery and is relatively cheap for this kind of thing at $89. See : http://www.datanumen.com/products.htm.

5. Stellar Excel Recovery - "Excel Recovery Software is designed to recover and repair corrupted Microsoft Excel documents. This advanced Excel spreadsheet repair program restores damaged Excel xls files after instances of virus attacks, unexpected system shutdown, media read error, and so on."  Newish too, I have not tried it.  $69.

6. R-Excel - "R-Excel is a tool designed to recover corrupted Microsoft Excel Sheets. New improvements of file reconstruction technology IntelligentRebuild allow the users to reconstruct damaged *.xls files and to restore lost Excel sheets quickly and easily. R-Excel safely performs any operation, including Microsoft Excel sheet recovery and never deletes from disk, writes to, or modifies in any way, the original Excel files." $79.  I think their other products are great, so this one should be too. Haven't tried it yet. Try the demo.

7. Kernel Excel Recovery - "Excel Fix software fix & repair excel file that gets corrupted or damaged. Kernel Excel Recovery is an excel fix tool to repair corrupt excel files created using MS Excel 2003, Excel XP, Excel 2000, Excel 97, Excel 95 that fails to open due to virus attacks, unexpected system shutdown etc." Starts at $49.

8. Repair My Excel - "Repair Excel files with Repair My Excel Microsoft Excel Recovery Software that will: Repair corrupted excel files Repair damaged excel files Repair Excel files from all versions of Microsoft Excel including 95, 97, 2000, XP, and 2003. Repair Excel errors like: "Unable to read file" "The document is corrupt and cannot be opened ..." Have not tried it.  Slick advert - $69.

9. EasyRecovery FileRepair v6.0 - is an excellent program which repairs all Office files including Outlook (pst) and Outlook Express (dbx and mbx) files. It also repairs corrupt zip files. It is relatively cheap for a suite of recovery programs: $299 but expensive if you are just fixing Excel files. It's available here: http://www.ontrack.com/datarecovery/servicequote.asp.  Hint: use the menu on the left to get to the programs Ontrack has available.  Will not fix any Office 2007 formats.  This technology may be falling behind now...

10. Excel workbook Rebuilder - this is the cheapest at about $30. I have not used it extensively but the new version has 4 different engines for recovering data, which is impressive. This program is really comprehensive with many expert features (VBA stuff), and maybe written for them. I haven't had much luck with it, but haven't tried it in awhile.

11. RecoverMyFiles - This program works differently then any of the others. It basically scours your hard drive for files and file fragments of a specified file type. Hopefully an uncorrupted previous file or file fragments still exists somewhere on your drive allowing you to recover or piece together your document.  

12. XLS Regenerator - is similar to RecoverMyFiles, but cheaper program and is just for Excel.

1. If these programs don't work to your satisfaction then your file is certainly corrupt, but don't despair there are professional Excel file recovery services or labs. They generally cost $49 and up per incident. Here are some:
   
   a.  socrtwo@s2services.com - this my service.  I do this for $22 but only use free methods because of my finances and legalities.
   
   b.  http://www.excelwordrecovery.com/ - $50 -$800.
   
   c.  http://www.repair-excel.com/ - Australian firm looks good. Don't know prices.
   
   d.  http://www.excel-rescue.com/ - Cimadevilla Electronica S.L. - Cimaware's parent company has an automatic cheap service costing $50 per file.  Recommended.
   
   e.  http://www.repairfiles.com/index.php - cheap service at $25 - 40. This guy seems to know what he is doing. He is the only one who explains his methods. Impressive explanation of Excel file structure.
   
   f.  http://www.ontrack.com - Ontrack has a service too. Click on the link on the left or on the button to start the easy quote process. May be expensive.

2. Finally if all else has failed, and you don't want to spend the money, you can use a freeware program to recover your text strings and figures (the figure recovery is theoretical) using a Text Extractor. My freeware Excel 2007 xlsx format freeware is really more or less an extractor.
   
   1. Corrupt xlsx2csv - my Excel 2007 to CSV converter.
   2. http://www.topology.org/linux/xls.html - Linux xlsx2csv if you are into that.  It might work with a corrupt file.
   3. DocToText - new find, true extractor of both numbers and strings I think.  Pretty cool.  My converter above works better at least with some xlsx files.  Don't know yet about of the efficacy with corrupt Excel 97-2003 files.
   4. BinText is definitely free but powerful.
   5.  TextExtract is another one.
   6. Readtext is a third.