When perform POS Posting, the system prompt me an error – “Line 2: Invalid Account No.”. What is the problem here?
Possible Reason :
This is most probably because one of your posting account number is missing
Please recheck all your posting account which is related to your Item and Discounts. For this case, the discount provided does not has an account to post to,
so most probably you will need to check your Default Discount Account under Tools > Options > GL > Default posting accounts > Sales Discount Account
Some other possibilities area where you can check:
Item Group Maintenance
Go to Stock > Item Group Maintenance > Edit and check all account mapped correctly.
Posting Account Group Maintenance
Go to General Maintenance > Posting Account Group Maintenance > Edit and check all account mapped correctly .
By: CK 20200323, Jacky 20200324 
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