LowLatenceLogger error message with Mega

I have a modified LowLatenceLogger sketch that works great with Uno and Due. With Mega, when terminating logging I get the message: error: Can't rename file.

Mega works fine when using the LowLatenceLogger example. My modified sketch uses a switch to start and stop logging. There's no keyboard interaction. Same sketch works OK with Uno and Due, not Mega.

Any ideas?

Thanks,
Gerry

Please disregard. All is good.