S7-1200 ‘Authorised Connection’ Password

3 posts in this topic

Hi guys

I could really do with some advice here

I visited a site earlier, having some problems with a system and I need to go online with the PLC to check the logic and find out what the issue is for a particular function of two separate machines.

I can find the IP address of the 1200 PLC with no issues, but as soon as I click ‘show’ or ‘detect’  a pop up window appears.

‘Authorised Connection

a password is needed to obtain HMI or diagnostic access to a protected device’

which of course I understand a company protecting their code. The issue now is that the company has gone bust and there is no way of contacting anyone that may have known the password.

So short of ripping out the perfectly good 1200 PLC’s (two systems) and replacing them with new logic (considerable more time required)


I am at a loss, does anyone know a work around for this?


Much appreciated 



Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now