So I've been fighting with this all day. I've tried 3 different machines including a server.
Basically when I try to access my ASA 5510 with the ASDM software the software never loads. So I have tried to access it through the management port https://192.168.1.2 and installed the software. The software starts up, I enter the password and it connects and loads to 100% but doesn't go beyond that point. I then try the java applet, and it as well loads up to 100% and says "Please wait, the main is coming up."
I have http server enabled, and asdm image is pointed correctly
As I said, I've tried this on two Windows XP machines and a machine running Server 2008.
I can connect through CLI all day and all night, but I'd rather (read feel much safer) configuring it through ASDM.
Here is some system version info
Cisco Adaptive Security Appliance Software Version 7.0(8)
Device Manager Version 5.0(8)
Compiled on Sat 31-May-08 23:48 by builders
System image file is "disk0:/asa708-k8.bin"
I would suggest you look and see if you meet the system requirements, especially for Java. If you do I would suggest loading a different version of ASDM on the ASA, that always seems to fix the problem you are experiencing.