I used to be able to just drag and drop audio files of various kinds into Sonar and it worked flawlessly. Since Hopkinton, I get errors such as "RIFF file create failed" for .wav and .mp3's and DirectShow error. Cannot playback the file. The format is not supported for M4a's. No matter how I import, I get these errors.

clear the picture cache

How do you do that??

Delete the contents of the directory defined in "Picture Folder" in Preferences > File > Audio Data

Did that. No Dice. Same behavior.

Are the files on the same drive as SONAR? If not, try moving the files to a different location before importing.

Both on the C: drive. I've never seen this behavior until Hopkinton

Roll back and see if it makes a difference

I have an older X3 version of Sonar on the computer as well. Just tried it out and everything works fine on it. Just not on Platinum H. Does it work on your computer?

Yes