Decryption of File Failed during Processing

Hi Folks,

We are having an issue when transferring file from CRM through webMethod to Tumbleweed.
We are getting following error:

------ Summary -------
Decryption of MEMBER_20090119110000-20090119130000.tsv.gpg Failed: 255 = Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-
interactive).
Decryption of ORDDET_20090119110000-20090119130000.tsv.gpg Failed: 255 = Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-
interactive).
Decryption of ORDHDR_20090119110000-20090119130000.tsv.gpg Failed: 255 = Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-
interactive).
Decryption of SUMMARY_20090119110000-20090119130000.tsv.gpg Failed: 255 = Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-
interactive).
Decryption Failed@gatewayService.ftpService.****Initiated.standard:decryptPgp

------ Log --------
Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-interactive).
Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-interactive).
Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-interactive).
Permission denied (gssapi-keyex,gssapi-with-mic,publickey,password,keyboard-interactive).
com.wm.lang.flow.FlowException:Decryption Failed@gatewayService.ftpService.****Initiated.standard:decryptPgp

Can anyone have a look into it and assist me in troubleshooting this.

Thanks,
-H