Hello dugaraochinna;

Is this the FM 350-2 configuration package you downloaded for your project?

https://support.industry.siemens.com/cs/ca/en/view/28554065

Can you tell us what version of Step 7 (v5.x or TIA Portal Professional) you are using, and the versio of Windows you have installed on your programming PC?

Siemens PLCs all have a helpful tool called the diagnostic buffer, it will have captured all faults on the CPU when they appear and will try to tell you the reasons they happen. You can use the CTRL + D combination on your keyboard to open the diagnostic buffer screen in Step 7, of you can look in the Step 7 menu the command to open it (check out the video below for step 7 v5.x)).

When you have opened the screen, yopu will see a button at the bottom showing "Save As..", click on it to generate a text file (Diagnose..txt) that will save all the diagnostic messages on your cPU. If you wish you can attach it here on a reply post so we can have a look at what the CPU is complaining about when you try to work with a FM 350-2. We might be able to help you understand the source of the problem.

Hope this helps,

Daniel Chartier