Hello there,
You need to tell the Publisher where to get the Certificate from:
Go to Project-> Properties
Go to the tab named “Signing”
Check the Checkbox labeled ‘Sign the ClickOnce manifests’. This enables the section where you can point to a certificate.
Click on the button labeled ‘Select From File…”. In the directory listing, choose a key file (.pfx) and Open.
From the step 3, click the button labeled “More Details…”. This will display the certificate you’ve just selected.
Click “Install Certificate” and follow the prompts.
Save and Publish your Solution.
I hope this information helps. If you have any questions please let me know and I will be glad to help you out.
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