How to change the value of Valuation class.

Question

dear friends:
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
Diagnosis
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
System Response
Your change is reset by the system.
Procedure
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.

Answer 1

To resolve SAP error message M3 368 I would suggest that you refer to SAP note number 1967543. This note outlines the issue and a resolution to it:
Please have a look at the description of the error M3 368. This error may occur if one or more of the following already exist for the material:
1. Valuated stocks in the current period or in the previous period
2. Open purchase orders or delivery schedule lines
3. Production orders for which a goods movement has already taken place
Resolution:
If you have valuated stocks in the current period or in the previous period, you will get message "Stocks already exist.". You have to clear all the stocks both in current period and previous period. Please have a look at SAP Note 30656, it shows an example on how to clear the stocks in
previous period. You can use transaction MIGO to execute this step.
If you have open purchase orders or delivery schedule lines, you will get message "Purchase orders already exist.". You can find related purchase orders after you click 'Display Error' button. Please delete them in transaction ME22N.
If you have production orders for which a goods movement has already taken place, you will get message "Production orders already exist.". Please archive these production orders. You need to set deletion flag for these orders firstly and go to SARA, use archiving object PP_ORDER to archive
these orders.
Kind regards,
James