I GOT IT!! yea!
I just changed it as follows...

FOR ....
nDividend = IIF( X > 0, nDividend - (X*(nBase^j)), nDividend)
ENDFOR


Thanks for the input.
Rick

---------------
>David,
>
>I've put together a routine, based on one that John Koziol attempted in message 139988.....
>
>*** Convert From Some Base (2-36) to Decimal (Base-10)
>PROCEDURE BaseToDecimal
>LPARAMETERS nBase, cBaseValue
>LOCAL nDecValue,i, BaseString
>nDecValue=0
>BaseString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
>
>FOR i = 1 TO LEN(cBaseValue)
> nDecValue=nDecValue+((AT(SUBSTR(cBaseValue,i,1),BaseString)-1)*nBase^(LEN(cBaseValue)-i))
>ENDFOR
>RETURN nDecValue
>
>
>But it goes in the opposite direction of what I want. I'm working on another routine....
>
>*** Convert From Some Base (2-36) to Decimal (Base-10)
>PROCEDURE DecimalToBase
>LPARAMETERS nBase, nDecValue
>LOCAL cBaseValue, i, j, X, BaseString, nRemainder, nDividend
>cBaseValue = ""
>i = 0
>j = 0
>X = 0
>BaseString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
>nRemainder = nDecValue
>nDividend = nDecValue
>
>DO WHILE nBase^i < nDecValue
> i = i + 1
>ENDDO
>
>FOR j = i to 1 STEP -1
> X = INT(nDividend/(nBase^j))
> nRemainder = MOD(nDividend, nBase) && or I could have said (nDividend % nBase)
> cBaseValue = cBaseValue + substr( BaseString, X+1, 1)
> nDividend = nRemainder && this line is wrong
>ENDFOR
>cBaseValue = cBaseValue + substr( BaseString, nRemainder+1, 1)
>RETURN cBaseValue
>
>But this isn't working yet...
>I know this has been done before...I hate reinventing the wheel!!!
>
>-------------------
>>David,
>>I need a base-36 number because it is used by an outside vendor as their unique identifier, and when I send my file to them it has to have this number.
>>---------------
>>>Rick,
>>>
>>>Why not just more simply use an integer field?
>>>-----------
>>>>I'm looking for a routine to convert a base-10 number to a base-36 number (0-9,A-Z). I need to create an incrementing counter in Base-36...or increment in base-10 and convert to base-36.