S7-1200 ‘Authorised Connection’ Password

[Phil_666]

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 

 

[Phil_666]

Well this isn’t looking good ;)

[mikemiranda0625]

try this...

the default Password of the Administrator User in TIA portal ist "Administrator".

Look at this FAQ:

https://support.industry.siemens.com/cs/de/en/view/10087466

 

In WinCC flexible 2008 and migrated Projects I agree its 100.

[hatta]

Hi All,

Same thing this happen to me, after i upgrade program from TIA v18 to V20 suddenly pop up window asking like that, i have tried all the password that i have like read access and know how protection it says password incorrect, is it the security setting by default? 
appreaciate someone can help me, thanks.

[Hati]

On 6/6/2025 at 4:31 AM, hatta said:

Hi All,

Same thing this happen to me, after i upgrade program from TIA v18 to V20 suddenly pop up window asking like that, i have tried all the password that i have like read access and know how protection it says password incorrect, is it the security setting by default? 
appreaciate someone can help me, thanks.

What did you try to access when it asked you for password? The HMI operating system has a few passwords that can be set to protect in different connections.

[hatta]

On 6/7/2025 at 1:02 PM, Hati said:

What did you try to access when it asked you for password? The HMI operating system has a few passwords that can be set to protect in different connections.

When I try to go online or download to my PLC, like suddenly all my password changed, also i cannot access web server with my current password

Edited June 9 by hatta
confidential

[Hati]

TIA20 has a lot of safety measures that can be activated in the PLC. You can reset the PLC to factury defaults, and you should be able to work with it again,