I have been using versions of Cakewalk's Sonar for years, and I've never had this problem. But now, every time I set up an audio track, arm it for recording, and press the "Record" button, I get an error message, saying "Unable to create new audio file for recording!". I have uninstalled the software from my computer, and re-downloaded it from Cakewalk Command Center; same result. I tried temporarily disabling my antivirus and firewall software, and that didn't make any difference. I also tried switching inputs and outputs from my usual audio interface (MOTU Ultra-lite mk3) to the built-in microphones and speakers with the laptop; no change.                My laptop is an HP Envy, with 12 GB RAM, Windows 8. It is three years old, but has been total refurbished, new RAM, new hard drive, new motherboard, and I have used Sonar Platinum with it since it's been fixed, and it worked fine. But then, a couple of weeks ago, I encountered this problem, and I can't I can't get it to work at all.                               This renders this supposedly high-end product utterly useless! I don't think Cakewalk has any tech support since it was bought by Band-Lab. Can anyone out there help me?

I would check to make sure the bit depths are the same in Cakewalk as in the interface.  ASIO is probably going to be the Driver you want. Lots of little things it could be. It should have a dedicated port for the interface. Could be a voltage issue from the computer to the interface. Loose connection.That MOTU is the hybrid model isn't it? Could be a setting in the interface.Is the hard drive almost full? 
I would try the MOTU with another computer to eliminate that as a possibility. Does Platinum still work with this setup? Was the OS changed in any way since it worked?

similar issue http://forum.cakewalk.com/FindPost/3746652
while

Tom Kallman
I tried temporarily disabling my antivirus and firewall software, and that didn't make any difference.

there may be another program interfering with SONAR such as the one mentioned near the end of the thread

Has the location of project audio always been the same? Could it be there's been, say, an external HD in use, which isn't available any more or something file-path related?

Thank you guys for the input; the problem has been solved! The link scook  posted  led me to Brian Johnston's earlier posts about a situation that was identical to my own, and the solution was also identical. An anti-malware program called ByteFence was the culprit. I didn't even intend to download it in the first place, but somehow it got installed on my computer. After uninstalling it, the problem was no more!       Any recommendations for free, or reasonably priced, anti-malware programs that don't interfere with Sonar and other musical software?