Cannot overwrite special file type by using Recuva

[Rocky BaLLi]

I have installed Recuva on my computer. I was scanning the hard drive for the files which are deleted. There was a file which were not important for me. the name of the file is Outlook Express emails.zip. it was WinRar archive for the default OE folders. Recuva was not able to delete the file and it was prompting with an error message and it can be stated as follow
Size - unknown Status - Not overwritten - Unable to overwrite special file type.
If you are having useful information then let me know about the same.

[AnitG]

You will not be able to securely delete zip file before you have recovered it. Recuva supposed to create zip file when you have supposed to select the recover email. If you are looking to recover the deleted emails then you should recover the same and zip it. it would be created at the time of recovery. Recuva would find pseudo-name for the zip filemane and hence it cannot be deleted securely.

[BillieJ]

I am assuming that recuva itself is writing on the file into overwrite operation. Free spaces on the hard disk is wiped with multiple pass checked or by using overwrite command of software.