No sound with audacity

I cannot start to record because the program easy there are errors with the sound. I have checked that my speakers are working and that their volumes are turned up. I have ckecked with the devise manager and this seems to be OK. What can be wrong, and how can I solve this problem?

What is the error message?
Which version of Windows?
Are you using Audacity 2.0?
When does the error occur?