[rabbitmq-discuss] Detect already installed version of RabbitMQ and Erlang during setup

[Simon MacMullen]

On 08/10/2013 09:38, Silverby, Patrik wrote:
> Hi,
>
> Is there a way that the RabbitMQ and Erlang installation can be detected
> by an installer to determine if they should be installed or not?

Our installer does this, see its source at 
http://hg.rabbitmq.com/rabbitmq-server/file/1bf3a1e2b9ed/packaging/windows-exe/rabbitmq_nsi.in

tl;dr: we check HKLM Software\Ericsson\Erlang\ErlSrv (with some version 
checking) and 
HKLM\Software\Microsoft\Windows\CurrentVersion\Uninstall\RabbitMQ.

Cheers, Simon