Continental-re hi,
thanks for posting this on q&a,
u might wanna check if u meet all the prerequisites first. sometimes the setup fails just cos the machine doesn't have enough resources or the right permissions.
if u're using a virtual machine, make sure its got at least 8gb ram and 4 cpu cores. also, the storage account u're using must be in the same region as the vault. small things like this can trip u up ))
another common hiccup is the connectivity. the appliance needs outbound access to specific urls and ports. if your network blocks any of these, boom, errors pop up.
check the logs in 'c:\programdata\asrsetuplogs'. they usually spill the beans on what went wrong. if u see something like 'failed to register appliance', it's often a certificate issue or expired tokens.
worth looking into your firewall settings too. sometimes antivirus software gets too excited and blocks the installation. temporarily disabling it might help (just remember to turn it back on after!).
and hey, if u're using a proxy, double check its config. the appliance might not be able to reach azure services if the proxy settings are off. this kinda thing bites everyone at some point )
last but not least, make sure u're running the latest version of the appliance software. microsoft rolls out updates pretty often, and the old versions can get cranky.
hope this helps,
rgds,
Alex