kp_XXXXX.tmp files related to Content Extraction can be found in default system or user temp folders: C:\Windows\Temp\ or C:\Users\SymantecDLP\AppData\Local\Temp\
It can be temporarily stored on DLP Detection Servers for example in:
C:\Users\SymantecDLP\AppData\Local\Temp\DetectionServerContentExtractionTemporary2233729003521219490\Keyview
or
C:\Windows\Temp\CDSContentExtractionTemporary1328111141775235362\Keyview\
Symantec DLP 15.8, 16.X
On each detection server, we can configure an exact path where all Content Extraction temp files will be stored. This is done by changing Advanced Server Settings of the detection servers. The setting which will be updated is ContentExtraction.TemporaryDirectory, where we can set a path value. That value should point to either a preexisting folder or to a newly created folder on the server. By default this value is blank.