oReXeRo: I have the same issue. Might this be caused by the fact that I use a 2 step varification which seems not to be supported by the embedded browser plugin?

sheva78: Thanks, this solution worked like a charm for me

Bustacap: reposting the newest version of the workaround for better visibility
----------------------

- close GOG Galaxy if it's running at the moment

- log in to the Playstation Store (store.playstation.com) through your browser
(if you were already logged in, log out first, then back in)

- after the login open this link: https://ca.account.sony.com/api/v1/ssocookie

youll get something like: {"npsso":"xxx"}
where xxx is the npsso value

(example of what it should look like: https://abload.de/img/npssomcj9f.png )

- open windows explorer and enter the following into the address bar at the top and press enter
%LocalAppData%\GOG.com\Galaxy\plugins\installed\

- open the psn_{random number} folder and edit the plugin.py file with your favourite text editor

- go to line 64. it sould look like this:
stored_npsso = stored_credentials.get("npsso") if stored_credentials else None

delete everything on that line after: stored_npsso =
then add your nppso value behind it in quotation marks.

it should look like this:
stored_npsso = "npsso value"

("npsso value" is the value from step 3 and should be a 64 character long text consisting of numbers, lower case letters and upper case letters)
(the quotation marks " " are important!)

(example of what it should look like: https://abload.de/img/plugingrjah.png )

- save the changes made to plugin.py and close the file
- restart GOG Galaxy
- try connecting with PSN again

Bustacap: unrelated

-------------------------------------

workaround until they fix it:

- close GOG Galaxy if it's running at the moment

- log in to PSN (store.playstation.com) through your browser
(if you were already logged in, log out first, then back in)

- after the login open this link: https://ca.account.sony.com/api/v1/ssocookie

youll get something like: {"npsso":"xxx"}
where xxx is the npsso value

- open windows explorer and enter the following into the address bar at the top and press enter
%LocalAppData%\GOG.com\Galaxy\plugins\installed\

- open the psn_{random number} folder and edit the plugin.py file with your favourite text editor

- go to line 64. it sould look like this:
stored_npsso = stored_credentials.get("npsso") if stored_credentials else None

delete everything on that line after: stored_npsso =
then add your nppso value behind it in quotation marks.

it should look like this:
stored_npsso = "npsso value"

("npsso value" is the value from step 3 and should be a 64 character long text consisting of numbers, lower case letters and upper case letters)
(the quotation marks " " are important!)

- save the changes made to plugin.py and close the file
- restart GOG Galaxy
- try connecting with PSN again

Bustacap: unrelated

-------------------------------------

workaround until they fix it:

- close GOG Galaxy if it's running at the moment

- log in to PSN (store.playstation.com) through your browser
(if you were already logged in, log out first, then back in)

- after the login open this link: https://ca.account.sony.com/api/v1/ssocookie

youll get something like: {"npsso":"xxx"}
where xxx is the npsso value

- open windows explorer and enter the following into the address bar at the top and press enter
%LocalAppData%\GOG.com\Galaxy\plugins\installed\

- open the psn_{random number} folder and edit the plugin.py file with your favourite text editor

- go to line 64. it sould look like this:
stored_npsso = stored_credentials.get("npsso") if stored_credentials else None

delete everything on that line after: stored_npsso =
then add your nppso value behind it in quotation marks.

it should look like this:
stored_npsso = "npsso value"

("npsso value" is the value from step 3 and should be a 64 character long text consisting of numbers, lower case letters and upper case letters)
(the quotation marks " " are important!)

- save the changes made to plugin.py and close the file
- restart GOG Galaxy
- try connecting with PSN again

Bustacap: unrelated

-------------------------------------

workaround until they fix it:

- close GOG Galaxy if it's running at the moment

- log in to PSN (store.playstation.com) through your browser
(if you were already logged in, log out first, then back in)

- after the login open this link: https://ca.account.sony.com/api/v1/ssocookie

youll get something like: {"npsso":"xxx"}
where xxx is the npsso value

- open windows explorer and enter the following into the address bar at the top and press enter
%LocalAppData%\GOG.com\Galaxy\plugins\installed\

- open the psn_{random number} folder and edit the plugin.py file with your favourite text editor

- go to line 64. it sould look like this:
stored_npsso = stored_credentials.get("npsso") if stored_credentials else None

delete everything on that line after: stored_npsso =
then add your nppso value behind it in quotation marks.

it should look like this:
stored_npsso = "npsso value"

("npsso value" is the value from step 3 and should be a 64 character long text consisting of numbers, lower case letters and upper case letters)
(the quotation marks " " are important!)

- save the changes made to plugin.py and close the file
- restart GOG Galaxy
- try connecting with PSN again

arjiwan: Close your GOG, then delete the GOG folder in your APP data

%LocalAppData%\GOG.com\

When you run Galaxy, it will recreate the folder.

Because the sso value has already expired. You need to create another sso value.

https://ca.account.sony.com/api/v1/ssocookie

oReXeRo: I have the same issue. Might this be caused by the fact that I use a 2 step varification which seems not to be supported by the embedded browser plugin?