Excel – Access file on a USB drive after drive removal

microsoft excelSecurityusb-flash-drive

Can an Excel file, opened from a USB flash drive, edited but not copied to the computer, be accessed after flash drive removal?

If I open an Excel file on my private computer with Windows installed, from a USB flash drive, edit it and save it to the flash drive but do not copy it to the computer, can then someone access or retrieve that file from my computer after I remove the flash drive?

If yes, then please tell me what to do to avoid someone from accessing it.

Best Answer

Can someone access or retrieve that file from my computer after the the flash drive is removed?

Yes.

Excel creates Autosave files (if configured to do so) and other temporary files. These files are deleted after Excel is closed but can be "undeleted" using data recovery tools.

See Recovering Excel documents that were closed without saving for more information.


Recovery of MS Excel Content from Temp Files

Microsoft have changed the way AutoSave and Auto Recover works in different versions of Office. Therefore you may want to experiment before you rely on this information.

Finding the Temporary Files

When a new file is started a temporary file is created. This can be either in the windows temp directory, or in C:\ Documents and Settings\<username>\Application Data\Microsoft. If the file is stored on a network drive then it will be temporarily created there.

This temporary file name will have a few different letters after a tilde (~) . These are good ones to look for to find some lost info. There are others, but these are the ones most likely to contain data that can be recovered.

Finding and using the temporary and auto save files

Excel doesn't have the AutoSave feature enabled as default, you have to add it. This is because it isn't always practical to have this functionality enabled. If you have it enabled and want to experiment with a spreadsheet, you should create a copy then open that so that the AutoSave doesn't overwrite the original.

To enable the AutoSave feature, you have to use an Add In. Go to "Tools" "Add ins" and choose "AutoSave".

With Office XP, AutoSave has been moved out from Add Ins to Options, in a similar way to Word. You will find the settings under "Save" where you can also disable the Auto Recover feature for that particular work book.

Excel automatically saves every 10 minutes to the default location of C:\ Documents and Settings\<username>\Local Settings\Temp or C:\Users\<username>\AppData\Local\Temp on Windows 7/Vista. The files are identifiable as they are saved as a number followed by .tmp e.g. 28.tmp. This means that they look different from word or any other temporary files that are being saved there by other applications.

The temp file for excel can also look like ~dfxxxx.tmp.

Office 2010 and Higher

In Office 2010 and higher, you have an additional option, built in to the product, called Recover Unsaved Spreadsheets

  • Click on File tab in the upper left corner.
  • Choose Recent
  • In the bottom left corner is Recover Unsaved Spreadsheets

The Saved Drafts folder will open. Find your file and double click on it to open. Then save the file.

These files can also be found in the following locations:

Windows 8/Windows 7/Windows Vista:

C:\Users\<username>\AppData\Local\Microsoft\Office\UnsavedFiles

Windows XP:

C:\Documents and Settings\<username>\Local Settings\Application Data\Microsoft\Office\UnsavedFiles

Other Useful Information

If you have been working on a file for hours and the document was created via copying and pasting or at one point had cut the entire page or document to paste some place and then placed something else on the clip board, the data may not have been lost. This is because when any info is copied it is sent to a temp file with the name ~wrlxxxx.tmp. Therefore you could search your system for files of this name and then use the same "Drag and Drop" technique to view the data in Notepad to recover the data.

Another interesting thing to note is that when a change is made to a document that requires a temp file to be created, when you press the save button all the temp files are merged together into one file and the file is renamed to what you called it. The original document that you created is then deleted.

Source Recovery of MS Excel Content from Temp Files

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