Add-in is not loaded and load log contains error

The digital signature file is corrupt error in the load log file

Sometimes, if you can't see the Ablebits tabs in the Excel ribbon, the problem may be in the corrupted digital certificate. The add-in may appear in the list of your available COM add-ins, but in the COM add-ins dialog window, you will see the Not Loaded. A runtime error occurred during the loading of the COM Add-In error message:
Not Loaded. A runtime error occurred during the loading of the COM Add-In.

Take the following steps to diagnose and fix the issue.

Step 1: Find the corrupted file

Paste %USERPROFILE%\AppData\Local\Temp\Ablebits into the Windows Explorer folder bar and open the Ablebits-ExcelUltimateSuite-load.log file:

Scroll the file to the end and check if there is the The digital signature is corrupt phrase:
The digital signature is corrupt.

If you find it, this means that you need to install the certificate. To find out the corrupted file, one line above the The digital signature is corrupt phrase, look for the file name in brackets:
Find the corrupted file.

Install the correct certificate

  1. Open the add-in installation folder. By default, if you haven't changed it while installing the add-in, it is
    C:\Program Files (x86)\Ablebits\Ultimate Suite for Microsoft Excel\

    Right-click the file that you found on the previous step and select Properties:
    Select Properties.

  2. Click the Details button:
    Click Details.
  3. Then click on View Certificate:
    View Certificate.

    You will see the Certificate Information:
    Certificate Information.

    Open the Certification Path tab. The root certificate will be marked with red:

    Certification Path.

  4. Select the marked certificate and click View Certificate. Then go to the General tab and hit the Install Certificate option that should be available:
    Install Certificate.

    Note. Please note, you should install the certificate in Trusted Root Certification Authorities store.
  5. Once the installation is done, the certificate will be no longer marked in red.

    If something went wrong or for any reason you were unable to install the certificate, you can download it from the DigiCert site:

    You'll need to install the DigiCert Assured ID Root CA:
    DigiCert Assured ID Root CA.