My very close friend just lost his excel file what he did is reinstall windows on drive C: the file were located on Desktop he come to me and I recover the file with correct size and name. But when we try to open the file it says the file is corrupted or damaged. what I can do to repair it?? any suggestion will be appreciated...

You don't say how you recovered it.
Maybe try a few different file recovery tools, but if you are using the same drive, booting up into windows, you will risk damaging it more.
Better off connecting the disk by USB adapter or whatever, booting in a different system and recovering with GetDataBack or rstudio, making sure to save to a different drive.

I am sure there are excel recovery tools and damaged file "fixers" available.

I'm not aware of it properly. but i can only tell you that there are many tools to solve this problem occurred in your laptop anyway try to solve it with the tools.

I try much tools but not success.

Is the data in the file sensitive? If not really, then upload here, someone can try fixing it.

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Hard Disk Drive (HDD), Solid State Drive (SSD, SATA, NVMe, etc), USB Flash Drive and RAID Data Recovery Specialist in Massachusetts

Odds are, you recovered the sectors where the file once lived, but those sectors have been overwritten with new data. Run a full scan of the clone for RAW Excel files and hope that you can sift through them to find one that contains the data you are looking for.

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Luke
Recovery Force Data Recovery

Ok I will upload the file after discussing with my friend. I already try full scan.

try to look inside the file (zip)

if you see the any content,
rename the file to .zip and make repair of the file by Winrar for example

Here is the file I attached my friend has travel agency and this is the record file. I recover some other files so he just continue his work. You can try to repair...

file has no header or the header is trashed. I see no way of fixing it.
It Is possible that the recovery software did not save the correct data, all the data or saved too much.

I think the file is overwritten the recovery software recover the file with no error... any other solution to fix this file all I know the size is ok.

Back to my original post, you will need to do a full RAW scan of the clone for Excel files. If you don't have a clone and the drive has been used since your first recovery attempt, I'd say that your odds continually decrease with each minute that the computer is running.

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Luke
Recovery Force Data Recovery

Yeah, no good. I thought it was more of a bad sector sort of scenario, but if it is overwritten, then chances are it will not work out.

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Hard Disk Drive (HDD), Solid State Drive (SSD, SATA, NVMe, etc), USB Flash Drive and RAID Data Recovery Specialist in Massachusetts

I often get clients who try to get me to "fix" files that they overwrote with their recovery efforts. I always request the original drive to work with for a few reasons:

1. I can see how much writing to the drive took place since the file deletion
2. I can see if they installed data recovery programs to the drive in question
3. I can see if they copied the recovered files directly back to the original drive
4. I can be sure that the drive in question clones with no read errors and possibly have bad sectors to be the original source of the problem (most common reason for re-formatted windows installs we get is because of undiagnosed bad sectors)
5. We can, at the very least, do a full RAW scan of the clone and try to find backup copies and file fragments

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Luke
Recovery Force Data Recovery

a blank excel 2007 document, when extracted (as a .zip file) expands to 6 folders with 11 files. The file is either going to need to be a slightly damaged zip file or pretty much perfect.

Unless the OP can recover the file from source again in better condition, then I think it is already game over.

a good excel file you can find the string "xml" in numerous places, and also see many consecutive 00's between the original files inside the zip, neither of which is present in the OPs file.

Remember that the answer "no solution" is a valid one.