It sounds like you may have run into a common issue with older Cisco ASA 5505 devices: finding a legitimate, safe, and working copy of ASDM (Adaptive Security Device Manager) along with the ASDM-IDM Launcher.
Grant Access to Your Workstation:Replace 192.168.1.0 255.255.255.0 with your actual network subnet and inside with your management interface.http 192.168.1.0 255.255.255.0 inside cisco asa 5505 asdm-idm launcher download
ssh version 2 and disable SSLv3.copy running-config tftp: regularly.Even without a contract, your ASA 5505 stores ASDM images locally. Use a browser that still supports Java (e.g., Internet Explorer 11 or an older Firefox portable build): It sounds like you may have run into
Java Runtime Environment (JRE): ASDM is a Java-based application. You generally need Java 8 (JRE 1.8) installed on your computer. Step-by-Step: How to Download the ASDM-IDM Launcher Upgrade to the final software: ASA code 9