We have this error when trying to write a temporary .har with Fiddler. We write a temporary file with Java using the ExeAction.exe with the name "out.har", rename it and then upload via FTP. However, sometimes we have a problem with the file being already used.
The error detail is attached.
We write the out.har using Java and Fiddler using the ExecAction.exe.
If you need anything else just say it, we've been struggling with this error for a while.