I have an interesting situation. I am using Office 2007 suite and installed the latest service pack (SP3) and now when I try to sign an InfoPath form, it tells me the signature is invalid.
"Before you can add a new signature, remove any signatures with invalid, error, revoked or not trusted signatures listed in status column"
After I get the above message. A signature is added to the form but the 'Signer' is filled in with '???' and then the form template locks up.
I have narrowed the issue down to a single DLL file in the OFFICE11 folder (msxml5.dll). When I go back to the previous version of the file (version 5.20.1087.0) the problem goes away. I make no other changes, just swap out the file and try to sign the form template and it works as expected. The signature issue only appears within a select few of my InfoPath form templates. I have done a manual comparison of the XML from a working signed form template and a non-working form template and do not see anything obvious that should be modified to get it working properly. Has anyone seen this before? It will not be acceptable for me to tell my client to not roll out a service pack because it will fail to add a signature to a few InfoPath form templates.
Thanks in advance for any and all help!