diff --git a/install.sh b/install.sh
index e70264c..48a80ec 100644
--- a/install.sh
+++ b/install.sh
@@ -15,17 +15,17 @@ LICENSE_DST="/Library/Preferences/Parallels/licenses.json"
 echo "[*] Kill Parallels Desktop"
 
 killall -9 prl_client_app 2>/dev/null
-killall -9 prl_disp_service 2>/dev/null
+sudo pkill -9 prl_disp_service 2>/dev/null
 
 echo "[*] Copy prl_disp_service"
 
-sudo cp -f ${PDFM_DISP_CRACK} "${PDFM_DISP_DST}"
+sudo cp -f "${PDFM_DISP_CRACK}" "${PDFM_DISP_DST}"
 sudo chown root:wheel "${PDFM_DISP_DST}"
 sudo chmod 755 "${PDFM_DISP_DST}"
 
 echo "[*] Sign prl_disp_service"
 
-sudo codesign -f -s - --timestamp=none --all-architectures --entitlements ${PDFM_DISP_ENT} "${PDFM_DISP_DST}"
+sudo codesign -f -s - --timestamp=none --all-architectures --entitlements "${PDFM_DISP_ENT}" "${PDFM_DISP_DST}"
 
 echo "[*] Copy licenses.json"
 
@@ -35,4 +35,3 @@ sudo chown root:wheel "${LICENSE_DST}"
 sudo chmod 444 "${LICENSE_DST}"
 
 echo "[*] Crack over"
-