Facing issue when joining Netbabackup 7.5 Software

Hello All,

Im facing issue with combination of 2 parts of NBU S/W, could any any suggest me on this .Below is the error

C:\Users\e821098>     copy /b "NetBackup_7.5_Win_zip.1of2"+"NetBackup_7.5_Win_zip.2of2" "NetBackup_7.5_Win.zip
The system cannot find the file specified.

C:\Users\e821098>
C:\Users\e821098>copy /b "NetBackup_7.5_Win_zip.1of2"+"NetBackup_7.5_Win_zip.2of2" "NetBackup_7.5_Win.zip
The system cannot find the file specified.

C:\Users\e821098>copy /b "NetBackup_7.5_Win_zip.1of2"+"NetBackup_7.5_Win_zip.2of2" "NetBackup_7.5_Win.zip"
The system cannot find the file specified.