Can't Run ASDM On New ASA

(2013-07-05)

Problem

Brand-new out-of-box ASA (5512 in my case) won't permit the ASDM to run. Error is:

Unable to load resource: https://192.168.1.1/admin/public/startup.jnlp

Solution

What is probably happening is the SSL Cipher settings on your browser are not permitting the SSL ciphers being served up by the ASA. Enable more modern ciphers on the ASA with this console command:

ciscoasa# conf t
ciscoasa(config)# ssl encryption rc4-sha1 aes128-sha1 aes256-sha1 3des-sha1
ciscoasa(config)# exit

...and try again.