Unable to import a certificate in ArcGIS Enterprise

Description

When attempting to import a certificate via ArcGIS Server Administrator Directory or Portal Administrator Directory, the following error is returned:

Error:   
Unable to import certificate. Code: 500

Attempting to import the same certificate via Internet Information Services (IIS) Manager returns the error message:

Error:   
The password you entered is incorrect.

Cause

This issue occurs when the following conditions are true:

• The ArcGIS Enterprise software is deployed on a Windows Server 2012 (R2) or Windows Server 2016 machine.
• The SSL certificate is created as a PFX file using the AES256-SHA256 encryption algorithm.

Solution or Workaround

Perform the workaround below to resolve.

1. Export the SSL certificate as a PFX file. Refer to Microsoft: To export the .pfx and .cer files for steps to do this.
2. When prompted to create a password in the Security window, select TripleDES-SHA1 from the Encryption drop-down list.

Once the export operation is successful, the PFX file can be imported into ArcGIS Enterprise and IIS Manager.