Question : Excel 2007 - Macro Digital Certificate Issue

I'm attempting to sign an Excel .xls spreadsheet and VBA project with a self-signed digital certificate that I created by using Office 2007's SelfCert.exe utility application.  When I try to save the spreadsheet after signing it using the certificate, I see this error message:  "There was a problem with the digital certificate.  The VBA project could not be signed.  The signature will be discarded."  

When I exported the certificate out of my certificates store, I chose the "DER encoded binary X.509 (CER)" option.  (See attached image).  Should I have chosen a different format?  Also, I did not export a private key (the option was grayed out when I ran the export wizard).

One other suspicion I have:  Is there a problem with signing an .xls spreadsheet with a certificate created by the Office 2007 SelfCert.exe application?  Maybe I can only do so with .xlsx formatted spreadsheets?  

Yet another thought:  Should I be saving the file as an Excel Macro-Enabled Workbook (.xlsm)?  

Many thanks experts!

Answer : Excel 2007 - Macro Digital Certificate Issue

Snoopfrogg,

How are you doing?

I noticed the Office 2007 - SP1, has some changes for for the utility, have you installed this service pack?
http://support.microsoft.com/kb/936982
Some KB's exist on the utility (very few, which suprises me, only 8 hits):
http://support.microsoft.com/search/default.aspx?InCC_hdn=true&Catalog=LCID%3D1033%26CDID%3DEN-US-KB%26PRODLISTSRC%3DON&withinResults=&QuerySource=gASr_Query&Product=xlw&Queryc=SelfCert.exe+&Query=SelfCert.exe+&KeywordType=ALL&maxResults=25&Titles=false&numDays=&InCC=on

Also - check this out:
http://vbadud.wordpress.com/

Sorry if these are not solutions, I figured I could get you at least going in the right direction!

Kevin