First you will need to configure voucher numbering automatic in BUSY,so you can follow given steps:
Step 1:Go to the Administration menu,
Step 2:Click on Configuration,
Step 3:Click voucher series configuration,
Step 4:Click on sales and select series,
Step 5:Click voucher numbering,Here you can set your voucher numbering automatically.
Step 6:Set numbering type automatic,
Step 7:Renumbering Frequency Set Yearly,select suffix or prefix,
Step 8:Mention seperator slash or highfin and year format,as you want.
Step 9:Suffix or prefix should be alphabaticaly,
Step 10:Select starting number and you can also set padding character in numbering if you wants,
step 11:Click ok,then window will appear,If you want to set voucher numbering from the beginning, please select the Re
numbering option as Yes,Other wise you can select as No.
Now, when you enter any voucher, the numbering will be generated automatically.