For some Saleae devices, the maximum sample rates are only available in certain configurations:
For Logic Pro 8 and Logic Pro 16, the maximum digital sample rate (500 MSPS) can only be selected when 4 or fewer digital channels are active and all analog channels are disabled.
If you are still not able to select 500 MSPS, it could be caused by using a USB 2.0 connection instead of a USB 3.0 connection. Review this article below.
For the new Logic 8, the maximum digital sample rate of 100 MSPS can be selected when 3 or fewer digital channels and no analog channels are active.
For Logic 4, there are no restrictions.
For the original Logic16, the maximum sample rate of 100 MSPS can only be selected when 3 or fewer channels are active.
The original Logic has no restrictions.
If you can select a sample rate but are unable to record at that sample rate (the capture ends with an error), please see this article below.