What is the user exit for automatic account determination in PO

Question

Hi Experts
   I ned to know  what is the user exit for automatic account determination in PO
my client needs the document type to defines Account Assignment Category.
choosen a document type Account Assignment Category is defined automatically.  you can't choose
a wrong  Account Assignment Category from the drop down list.
thanks form you help.

Answer 1

If this is the case than why don't you use the Transaction variant
SHD0: http://www.mortenhjorthnielsen.dk/Security/transactionvariants.htm
If you have knowledge of Transaction variant then you can use SHD0 tcode and generate the transaction using default type and give that transaction to user instead of ME21N so they will not have the issue.
The exact solution for your problem is as follows
Go to Tcode SHD0 and enter the transaction variant
In T code field enter ME21N and then enter the ZXXXX or the name you want to keep in transaction variant field and hit create button
This will take you to ME21N transaction and here you just enter the data but make sure you enter the A/c which you want to default.
Once you finish system will save this one as a variant
Every time you hit or enter the pop up screen comes here you just hit enter and whichever data you want to default that you have to select in the Popup by checking the Box
W content and output only for your case the field XXXXXXXX should be selected for W content and output only
Make sure you have value 1 in contents field
If not then restart the variant again and on the ME21Nscreen reselect the invoice field
Later exit and save (save in the object which you can transport)
Then from SHD0 transaction select GOTO create variant transaction and here you careate the tcode and use that tcode for ME21N (e.g ZTRAN - For specifix sto)