Keyview normally assigns a temp directory creates temp files during some internal filter processes, this is expected. During normal processing the temp files are removed however under some exception circumstances, for example if the kvoop.exe or parent process (in this case the Data Protection Policy Engine) are killed unexpectedly, the temp fails may not be removed.
Additionally there are some known issues around processing some formats (i.e. MS Office formats like DOCX, XLSX) where some temp files are generated and fail to be removed after processing. This is a known issue with the 10.2x release of Keyview which is embedded in CA Data Protection 14.x and 15.x and will be addressed in future releases of Data Protection.