So, we have a couple Cisco ASA 5510 security appliances that we are working on. Here is the catch, when you attempt to connect to them using the ASDM tool downloaded from the device (or the CD from Cisco, or a download from Cisco’s website) you get a connection error “ASDM cannot read the configuration from the ASA”. After ensuring that the networking was indeed correct and I could reach the device I discovered (after several hours) that the ASDM is java based and that the version of java that I was using (Java 6 Update 11) was simply too new for the ASDM. To fix this I had to downgrade my java to Java 5 Update 17 and bingo, the ASDM could now talk to the ASA.
Next I was able to upgrade the via the ASDM the ASA’s Software and ASDM software. Once updated to the newest versions (8.01 and 6.1551 respectivly) I was able to re-download the ASDM client from the device and use the newest java version.