''Unable to configure RSA server private key''

Resolution:  
To resolve this problem, specify the correct private key for the certificate.

1. View the certificate modulus using the following command:
   
   

   openssl x509 -noout -text -in certfile -modulu
2. View the key using the following command:
   
   

   opensslrsa -noout -text -in keyfile -modulu

Verify the following: 

1. Verify that the certificate and private key is saved in Notepad and that it has no trailing spaces. 
   
2. The "modulus" and "public exponent" portions in the key and the certificate must match exactly. 
   
3. Make sure you aren't using the default server.key file. 
   
4. You should also check the httpd.conf / httpd-ssl.conf file to make sure that the directives are pointing to the correct private key and certificate.