Product:
Cognos TM1 10.2.2 Fix Pack 6
Cognos BI 10.1.x
Microsoft Windows 2012 R2 Server

Symptom:
When try to create a data source connection to a new setup TM1 10.2.2 server (with fix pack 6) from an old Cognos BI 10.1 server. You get a error.

Error message:
XMD-CON-0001 Connect failed with error message: TM1-ERR-0070 The TM1 server srv100/planning sample cannot be found.

Solution:
Add this parameter to the TM1S.CFG file for the TM1 instance (planning sample)
SupportPreTLSv12Clients=T
And restart the service.

You also need to set TRUE on Support pre-TLS v1.2 clients
In the Cognos TM1 configuration, like this

To allow TM1 clients and TM1 servers prior to 10.2.2 FP6 to connect to a 10.2.2 FP6 TM1 Admin Server:
1. Click Start > IBM Cognos TM1 > IBM Cognos Configuration.
2. Click TM1 Admin Server on the Explorer tree in Cognos Configuration.
3. Set the Support pre-TLS v1.2 clients property to True.
4. Click File > Save.
5. Click File > Exit.
6. Click Yes if prompted to restart the TM1 Admin Server.

More info
http://www-01.ibm.com/support/docview.wss?uid=swg27048181