Error: this may be caused by a missing self-signature

[zoeyyl.hung at jpmorgan.com]

Dear support,

There is an error "this may be caused by a missing self-signature" when
partner sides import my public key?
They are using currently using gpg 1.4.7 under Windows Server 2003, my
questions are:

1) why causes the error?
2) Is it because they are using windows server 2003? can windows server
2003 works smoothly for gpg? as I see the supported systems exclude
that...Pls advise, thank you.

YL

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