How to delete a file that contains a backslash in the name under Windows 7? [duplicate]

How about running CHKDSK?

There was a similar question here: How to force Windows to rename a file with a special character?, one of the answers to which demonstrated that CHKDSK deletes files with invalid characters in their name.

I would try using short 8.3 naming:

del worksp~1.zip

since that does not seem to work for this specific file, the next thing that I would try is to open a Powershell command prompt then do:

Get-ChildItem G:\Z_Drive\* | Where-Object{$_.Name -Like 'workspaces*'} | Remove-Item -WhatIf

Be sure to play around with the pattern so that you are only matching that one file (not sure if there are other files in there or not). Once you see that it would only try to delete the one file, remove the -WhatIf

open a cmd, do dir/x and find the short name of the file, and delete that.

Could you try renaming it?

rename *.zip tmp.zip

did you try with powershell? if not, try :

First move to the folder, then start powershell (typing powershell, enter) then copy it:

ls | ?{$_.name -like "*\*"} | %{$_.delete()}