>>I tested this. As Gregory says the likilihood of getting two consecutive identical results is purely statistical. With a password length of 5 I get a duplicate once every 40-150K operations. With a password length of 10 I'm currently past 12,000,000 without a duplicate.
>>I guess it shouldn't be hard to calculate the actual odds - but you get the picture.
>>
>>Even with a 5 character password does having one duplicate per several tens of thousands of instances really present a problem?
>>And you're going to get duplicates anyway - why does the fact that they may be generated consecutively matter?
>
>The issue is not about getting unique values on a long period. It is in regards to an issue I have when I need to include a default value for a username and a password in a page. Thus, I call the same method twice. So, I needed to avoid receiving the same values back.

Hi,

So what password length are you using? Even a length of 7 puts the odds at several million to one.
If that's not good enough you could include numbers and/or case sensitive alphas.
But how many users are you expecting and what are the real consequences of generating two identical consecutive passwords?
Do you envisage either party being able to make use of the fact (even if they knew it had occurred)?
IAC, if you really cannot accept consecutive identical values then you have no option except to check them as they are generated.

Regards,
Viv