Product:
Planning Analytics Workspace 2.0.9.3

PAA Agent Version 2.0.63.1420
Microsoft Windows 2019 server

Issue:
This request cannot be understood by the server. This might be because there is a problem with the syntax. Retry this action.

Above error when you in PAW click on Administration – Databases – Planning Sample – Configuration.

Solution:
The user who login to PAW need to be local Admin inside the TM1 instance, to be able to see and change the configuration (tm1s.cfg) from the PAW administration page.

Go into Tm1 Architect, open the TM1 instance, right click and select security – Clients/Groups:
Find your username, and mark that you are ADMIN.
Click OK.

The user can restart the TM1 instance from PAW, without being ADMIN inside the TM1 application.

More information:

https://www.ibm.com/docs/en/SSD29G_2.0.0/com.ibm.swg.ba.cognos.tm1_inst.2.0.0.doc/tm1_inst.pdf

https://www.ibm.com/docs/en/planning-analytics/2.0.0?topic=workspace-monitor-administer-databases