Data inconsistancy between material master and material ledger

Hi Gurus,

When I try to open the material with accounting view in MM03 the system is giving with an warning message "Valuation of material A in valuation area B inconsistant". and when I try to open with MM02 its giving the same message as error message, Its not allowing me to change the material.

This is due to differences in the material ledger and material master valuations.

Request any one can advise me how these differences can be neutralised.

If you need any details let me know..

Regards,

Nag.