>>>Yes, I do have the file size which is 3,857,493,504.
>>>But during encryption it reads until 10,772,236,288
>>>
>>>That is what still causes me trouble, maybe I miss something.
>>
>>You are right! Sorry.
>>
>>The correct computation is:
>>

>>* start
>>n4GB = 0
>>nSign = 1
>>
>>*EXECUTE
>>IF m.nSign#SIGN(m.nZipBytes)
>>	IF m.nSign=1 AND SIGN(m.nZipBytes)=-1
>>		n4GB = m.n4GB + 4294967296
>>	ENDIF
>>	nSign= SIGN(m.nZipBytes)
>>ENDIF
>>
>>nZipped = m.nZipBytes + m.n4GB
>>
>>zipRatio = m.nZipped / m.fileSize
>>

>
>Like a charm, thanks for your great help!

You're welcome.