When running the normal archive task I get the following error in relation to an email in a users inbox. I have looked at the email and all seems normal but it will not archive. The rest of the inbox archives fine. Any ideas what would cause this.

19:23:47: Mailbox: Mike Grant/GBR - mail\mgrant.nsf
Unable to create ONM file: CreateMsgDocument - Unknown error
Notes server: gb001sv0016.ns.tpnet.intra
Notes server port: CN=SGABZ01/O=GBR
Notes mailbox: MGrant
- Re: Fw: Hydro Peregrino Tender -

Cheers