Decrypt issue: Please enter name of data file ?

[Arun Kumar Moothedath]

I am trying to decrypt an encrypted file with following statement.

gpg -o "D:\test\out\Test.xml" --passphrase-fd 2 2<"D:\test\passtest.txt" 
--decrypt "D:\VZ\test\Test.xml"

It works fine for most of the files. Yesterday onwards I am getting an issue 
with some of the files.

The message is

Detached signature.
Please enter name of data file:

And it expects the file name as a user input.

Why is it happening and what is the solution.

Thanks
Arun.