Warning: only do this if YOU trust the certificate.

Don't do it for any random certificate as this can be a security issue and is not actually required if you just want to view the PDF.

I can sign the pdf fine using the cert but when another user opens the document I get the error "At least one signature has problems".

In the Signature Panel I see "Signer's identity is unknown because it has not been included in your list of trusted identities and none of its parent certificates are trusted identities".

It appears to me I need to add either the root or intermediary CA as a trusted identity.

However, when I try to add it, neither certificate appears in the list from which to choose.

Secondly, if a digitally signed document has been altered in anyway, a warning will be clearly visible.

For security purposes, by default, Adobe automatically does not trust anyone.After signing a PDF file and then opening it in Adobe Reader or Adobe Acrobat the following message may be shown just below the toolbar: At least one signature has problems This message does not indicate that the digital signature is invalid or corrupt.Instead it's a poorly worded message from Adobe that causes unnecessary alarm.You filed your return in a timely manner and were waiting for your refund to be sent within the standard timeline that IRS promises.But alas, it has been much longer than that and you are wondering, “Where is my DAMN refund!If you agree to trust all root certificates in the Windows Certification Store, select OK. Click on the full size file, select the signature icon, select the signature line and then right click to bring up the short-cut menu. If you trust the identity of the signer of the document, select OK.5.