i want to change the value of Valuation class in the material master .but system warning info occurs .
The valuation class cannot be changed
Message no. M3 368
You wanted to change the valuation class. However, this is not possible because one or more of the following already exist for the material:
Valuated stocks in the current period or in the previous period
Open purchase orders or delivery schedule lines
Production orders for which a goods movement has already taken place
Your change is reset by the system.
If valuated stocks already exist, you can change the valuation class only as follows:
a) Post the stocks of the material to an interim account.
b) Change the valuation class in the material master record.
c) Post the stocks of the material back to their original account.
If open purchase orders already exist, you can only change the valuation class if you first flag the corresponding purchase order items for deletion.
If production orders exist for which a goods movement has already taken place, you can only change the valuation class if you first set the status of the production orders to Deleted.
Procedure for System Administration
In Customizing for the Material Master, you can switch the check for open purchase orders and/or for production orders to a warning. You do this in Define Attributes of System Messages by assigning the message type Warning to message MM 326 and/or MM 327 respectively. However, first ensure organizationally that further processing of the open purchase orders or production orders cannot result in inconsistencies.