Product:
Cognos TM1 10.3 in the cloud
Microsoft Windows 2012 R2 Server

Symptom:
When user run a TI process from a button on a web sheet (TM1WEB) there is a error “Process Fail”, but if a ADMIN user run’s it then it works.
There is no error in log files.

Cause:
The user does not have READ rights on the TI process.

Solution:
Login to TM1 Architect as ADMIN
Right Click on Processes and select Security Assignments
Go down to the line for your TI process.
In column Cognos\Everyone_CAMID(_Everyone)
Set READ
Click OK

By setting READ people in that Security Group can run the process.

More Information:
http://www.ibm.com/support/knowledgecenter/SS9RXT_10.3.0/com.ibm.swg.ba.cognos.tm1_dg_dvlpr.10.3.0.doc/c_tm1_dev_datares_modes.html

With the later TM1 10.2.x versions you have a function called
Data Reservation modes
Data Reservation modes allow you to configure the Data Reservation feature depending on how you want to control write-access to your data. When you enable the Data Reservation feature for a cube, you choose one of the available Data Reservation modes.

The available Data Reservation modes include:

Off (OFF)
Required (REQUIRED)
Required Shared (REQUIREDSHARED)
Allowed (ALLOWED)

You can create a TI process with this value in PROLOG to set the value to blank for your Cube:

sValue = ”;

cellputs ( sValue, ‘}CubeProperties’, ‘Demand Plan’, ‘DataReservationMode’);

Change ‘demand plan’ to the name of your Cube in the TM1 application.