You are right Ajay. But let me explain here.
As I explained above was the original situation in my production system.
Then we have replicated the same issue lower environment with production system.
Then I have started trying with various options.
1option I did was, I picked a particular asset and checked in AW01N and seen that there is a depreciation entry posted for 12/2016, but ONLY in Asset not in FI as FI period 12/2016 not yet opened.
Then I have changed the dep.key from LINA to 0000 on asset master (AS02) in lower environment system.
Ran AFAB planned depreciation for 12/2016. Now the posted depreciation amount has gone.
I flipped back the dep.key from 0000 to LINA and then I tried the AFAB planned dep for 1/2016.
Then the error message is different on which you have commented above.
Hope this explains the scenario how the error message is showing in the attachment.