Indeed, there's no way in Explorer to 'unlock' a file, as far as I know.
The next steps:
1. Can you open that file after a reboot?
2. Can you open that file after you close Photoshop? If no, continue with:
3a. Download and install Process Explorer from http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx.
3b. Use it to find if there's a program having it open.
3c. If so, delete that program from Task Manager.
3d. See what happens.
Also try unlocker from http://www.softpedia.com/get/System/System-Miscellaneous/Unlocker.shtml and see how that works.
Tell your experiences.
Kees
Hi, recent problem with photoshop 6. Working well before for years. When I open a TIF file and save as jpeg, somtimes I won't be able to re-open the jpeg. I get an error message that says 'could not open "C:file path\filename.jpg" because the file is locked. Use the 'properties' command in the windows explorer to unlock the file'.
However, even when looking under the properties command for that file, I can't find anywhere to 'unlock' the file. I can't delete the file either. I've also tried to open as a TIF or to open with other programs such as paint or picasa, with no luck. I then uninstalled photoshop and re-installed it - no improvement.
System - Lenovo T61 laptop T7500@2.2 GHz, 2GB RAM, WinXP Professional SP2, Photoshop 6.0

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