How can I transfer balance of customer, vendor and ledger from previous accounting system to sap r/3 envioroment?

1. Prepare the Balance Sheet at one cut off date.

2. Classify the Accounts into Group.

3. Create Group wise clearing GL (You should create clearing account through OBD4)
      for eg.  Capital General Clearing A/c
                 Capital Initial Clearing A/c

                 Expenditure General Clearing A/c
                 Expenditure initial clearing A/c

                 Customer General Clearing A/c
                 Customer initial Clearing A/c

                 Create the GL each Account Group.

4. Create one Doc.Type "LD"  for upload Legacy Data.

5. Post the Balance Sheet Figures through T.Code F-02 use Doc.Type "LD"
      for eg.  Sundry Debtors Balance Rs,5 lac in Balance Sheet. This fig was arrived from 5 
                  customers   Mr.A - Rs.75,000 Mr.B Rs.25,000 Mr.C Rs. 400000

                  Post

                  Customer General Clg A/c   Cr.5,00,000
                  Customer Initial Clg A/c        Dr.5,00,000

                 Like that post all the Balance Figures in SAP group wise. Maintain one XL Sheet. Carefully maintain this sheet.

                 All the General Clg GL figures are opposit to BS, only for controlling

                 Then post

                  Customer Inital Clg A/c Cr.                                   5,00,000

                   Mr.A                    A/c     Dr.      75,000 
                   Mr.B                    A/c     Dr.       25,000
                   Mr.C                    A/c     Dr.    4,00,000

After completed the posting all the inital accounts are "0" Value and all the General Clg A/c are "0".

If you want to post the Customer open item line by line, prepare the XL sheet upload through LSMW.

If you want to check the TB in SAP to Tally, select all the document and filter the Doc.Type "LD" the debit balance and credit balance are "Zero".

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