Ok, I found the application in the "admin tools".
Here are the logs.
First, application log.
All error for august are ieplore.exe hangs (6 of them).
July, 31st: one error:
Application halted alcupd.exe, version 1.7.0.0, module halted hungapp, version 0.0.0.0, adresse de blocage 0x00000000.