Error Capturing Image

I'm going throught the steps and I'm at the task in the step to capture the image where you have to type one of the commands from table 2 into the command prompt. It says scanning files and directories... and then after a couple minutes I get an error message as follows: [ERROR] C:\ProgramData\Microsoft\Microsoft Antimalware\IMpServiceEDB4FA23-53B8-4AFA-8C5D-99752CCA7094.lock (Error = 32) Error imaging drive [C:\] The process cannot access the file because it is being used by another process.