Product:
Cognos Controller 10.2.1 Fix Pack 4
Microsoft Windows 2012 R2 server

Symptom:
Error when importing csv file with data, that have worked fine in previous version of Cognos Controller 10.1. The DiscardedRows are the same number as the Rowsread in Log Reports dialog.

Error message:
The value must be numeric.

The data we try to import contain a decimal value; e.g. 000.00

Solution:
Log on to the Cognos Controller server as the service account that run the Cognos Controller services.
Go to controller panel
Go to regional settings
Change to England (UK)
Click tab ‘Location’
Change this to ‘English (United Kingdom)’
Click tab “Administrative”
Click “Change system locale…” and change this to “English (United Kingdom)”:
Click “Copy Settings”
Tick the box “Welcome screen and system accounts”.
Tick the box “New user accounts”:
Click OK
Reboot the Controller application server

I think it is the value of Decimal symbol need to be changed from comma to a period that solves the issue.

The csv file that is imported to controller must be of a specific format.
Text file should use decimal point (not comma) for decimals and semicolon (not comma or
tab) as delimiter between the data fields.

More information:
http://www-01.ibm.com/support/docview.wss?uid=swg21691867