Thumbnails failure in MPC

Hi,
The function "Save Thumbnails " in MPC is not working in the revision K-Lite Codec 18.6.5 (MEGA)
I have returned for 18.6.2 , that works normally.
this is it.

It still works fine here.

You need to give more details.
What error do you get?
Which video renderer?
Which size video?
Which size thumbnail and how many columns/rows?

A window is diplayed with the following information:

AN ERROR OCCURRED MPC-HC WILL CLOSE NOW
EXCEPTION : ACCESS VIOLATION
CRASHIN MODULE: C/ PROGRAM FILES (X86) \K LITE CODECK PACK \ MPC-HC64.EXE

OFFSET : 0X7B6A1, CODE BASE: O7FF742690000
THE THREAD 25824 TRIED TO READ MEMORY AT ADDRESS 0XC

Which video renderer? mkv, 1080p


Which size video? 2Gb


Which size thumbnail and how many columns/rows?

jpeg, 960 pixel, 2/2