@avinashdalvi_​ Which workspace couldn't be opened? Was it last edited with a build newer than 16167?

You can also try viewing the workspace in a text editor and check the file size.

Nothing change in file. Only thing it is AWS EC2 machine. Cloud Ops team is performing upgrade on backup of this EC2 to window 2012 os. suddently this appeared

File size is correct. I tried copying that file to other local machine it works there perfectly.

Can you open other workspaces in Workbench? Can you view this problem one in a text editor?

Text editor I can open file. Only problem while opening Workbench and Through command fme.exe

Can you open the workspace on another machine? Can you attach it here? thanks

I tried to copy that workspace on MacBook it work there.

@avinashdalvi_​ Does the MacBook also have build 16167 installed, or is it newer? Which command are you using to open the workspace from the Windows command line? Can you share the workspace? thanks

This is not related to version it is sudden behaviour. If run fme.exe as administrator its work