Excel 2007

Steps taken: Created a certificate called XYZ (which I thought enable my Excel Macros)
which was placed in my Personal Certificates Store but forgot how I did that a year ago.

Now almost every previously created Excel w/s I open contains the message:

"Data connections have been disabled"

Bottom line - how do I get around this issue??

Also, I have deleted all data connections (in a workbook), saved the file, then re-opened
it only to find the same data connections.

ADDITIONAL STEPS:

I have heard that the solution may involve the MS Certificate Manager.

Therefore I used "certmgr.msc" (from STARTRUN) certmgr.msc and I would like to install
my certificate into "the trusted Root Certification Authorities store".

I can see the certificate in the Personal folder but its "certification path" indicates
that it is "Not Trusted."

Do I have to delete it and start over? modify it?

I have no clue how to:
1) create, modify a personal certificate and/or
2) install it in the trusted Root Certification Authorities store and/or
3) make sure that the "certificate path" is OK (in short authorized and OK)


TIA EagleOne