It is always recommended that you backup your data before upgrading Windows. But if you did not and if you have just upgraded to Windows 7 and find that for some reason, your data is missing after the upgrade, here are a few troubleshooting steps you may want to try out.

1. See if you can retrieve your data from the Windows.old folder.

2. In case of incomplete data migration, you can search for data files using DIR in the \$Windows.~Q and \$INPLACE.~TR folders.

3. In case you are unable to locate data in the above-mentioned two steps, use an Administrator command prompt to perform a check on the entire drive for the missing data files.

For instance to check for images:

Cd\
Dir *.jpg /a /s > %userprofile%\Desktop\jpg_files.txt

4. If you can identify the location where the data has been copied, use drag and drop or robocopy.exe to help put the files in a more accessible location.

5. If you cannot locate any data files on the machine, check the \Windows\Panther\Setupact.log file and ensure that this was indeed an upgrade installation. If not, you can determine whether the partition was formatted in the log, as well as know to check other partitions for the data.

For some more information visit related article KB930890 – Some files may appear to be missing after you upgrade an earlier version of Windows to Windows Vista.

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