I post the log :
=== Verbose logging started: 26/01/2016 19:28:38 Build type: SHIP UNICODE 5.00.7601.00 Calling process: C:\Windows\system32\msiexec.exe ===
MSI (c) (D0:9C) [19:28:38:779]: Font created. Charset: Req=0, Ret=0, Font: Req=MS Shell Dlg, Ret=MS Shell Dlg
MSI (c) (D0:9C) [19:28:38:779]: Font created. Charset: Req=0, Ret=0, Font: Req=MS Shell Dlg, Ret=MS Shell Dlg
MSI (c) (D0:48) [19:28:38:784]: Resetting cached policy values
MSI (c) (D0:48) [19:28:38:784]: Machine policy value 'Debug' is 0
MSI (c) (D0:48) [19:28:38:784]: ******* RunEngine:
******* Product: AcroRead.msi
******* Action: ADMIN
******* CommandLine: **********
MSI (c) (D0:48) [19:28:38:789]: Machine policy value 'DisableUserInstalls' is 0
MSI (c) (D0:48) [19:28:38:794]: SOFTWARE RESTRICTION POLICY: Verifying package --> 'C:\AcroRdrDC1501020056_fr_FR\AcroRead.msi' against software restriction policy
MSI (c) (D0:48) [19:28:38:794]: SOFTWARE RESTRICTION POLICY: C:\AcroRdrDC1501020056_fr_FR\AcroRead.msi has a digital signature
MSI (c) (D0:48) [19:28:38:824]: SOFTWARE RESTRICTION POLICY: C:\AcroRdrDC1501020056_fr_FR\AcroRead.msi is permitted to run at the 'unrestricted' authorization level.
MSI (c) (D0:48) [19:28:38:829]: Cloaking enabled.
MSI (c) (D0:48) [19:28:38:829]: Attempting to enable all disabled privileges before calling Install on Server
MSI (c) (D0:48) [19:28:38:829]: End dialog not enabled
MSI (c) (D0:48) [19:28:38:829]: Original package ==> C:\AcroRdrDC1501020056_fr_FR\AcroRead.msi
MSI (c) (D0:48) [19:28:38:829]: Package we're running from ==> C:\Users\Jack\AppData\Local\Temp\a8ef9e.msi
MSI (c) (D0:48) [19:28:38:829]: APPCOMPAT: Uninstall Flags override found.
MSI (c) (D0:48) [19:28:38:829]: APPCOMPAT: Uninstall VersionNT override found.
MSI (c) (D0:48) [19:28:38:829]: APPCOMPAT: Uninstall ServicePackLevel override found.
MSI (c) (D0:48) [19:28:38:829]: APPCOMPAT: looking for appcompat database entry with ProductCode '{AC76BA86-7AD7-1036-7B44-AC0F074E4100}'.
MSI (c) (D0:48) [19:28:38:829]: APPCOMPAT: no matching ProductCode found in database.
MSI (c) (D0:48) [19:28:38:834]: MSCOREE not loaded loading copy from system32
MSI (c) (D0:48) [19:28:38:834]: Machine policy value 'TransformsSecure' is 0
MSI (c) (D0:48) [19:28:38:834]: User policy value 'TransformsAtSource' is 0
MSI (c) (D0:48) [19:28:38:834]: Original patch ==> C:\AcroRdrDC1501020056_fr_FR\AcroRdrDCUpd1501020056.msp
MSI (c) (D0:48) [19:28:38:834]: Patch we're running from ==> C:\AcroRdrDC1501020056_fr_FR\AcroRdrDCUpd1501020056.msp
MSI (c) (D0:48) [19:28:38:834]: Opening existing patch 'C:\Windows\Installer\c9d9f.msp'.
MSI (c) (D0:48) [19:28:38:834]: SequencePatches starts. Product code: {AC76BA86-7AD7-1036-7B44-AC0F074E4100}, Product version: 15.007.20033, Upgrade code: {A6EADE66-0000-0000-484E-7E8A45000000}, Product language 1036
MSI (c) (D0:48) [19:28:38:834]: PATCH SEQUENCER: verifying the applicability of minor upgrade patch C:\AcroRdrDC1501020056_fr_FR\AcroRdrDCUpd1501020056.msp against product code: {AC76BA86-7AD7-1036-7B44-AC0F074E4100}, product version: 15.007.20033, product language 1036 and upgrade code: {A6EADE66-0000-0000-484E-7E8A45000000}
MSI (c) (D0:48) [19:28:38:839]: PATCH SEQUENCER: minor upgrade patch C:\AcroRdrDC1501020056_fr_FR\AcroRdrDCUpd1501020056.msp is not applicable.
MSI (c) (D0:48) [19:28:38:839]: SequencePatches returns success.
MSI (c) (D0:48) [19:28:38:839]: Final Patch Application Order:
MSI (c) (D0:48) [19:28:38:839]: Other Patches:
MSI (c) (D0:48) [19:28:38:839]: Unknown\Absent: {AC76BA86-7AD7-0000-2550-AC0F0A4E5800} - C:\AcroRdrDC1501020056_fr_FR\AcroRdrDCUpd1501020056.msp
La mise à niveau ne peut pas être installée par le service Windows Installer car le programme à mettre à niveau est absent, ou la mise à niveau est prévue pour une version du programme différente. Vérifiez que le programme à mettre à niveau existe sur votre ordinateur et que votre mise à niveau est valide.
C:\AcroRdrDC1501020056_fr_FR\AcroRead.msi
MSI (c) (D0:48) [19:28:38:839]: Produit : Adobe Acrobat Reader DC - Français - La mise à jour ‘{AC76BA86-7AD7-0000-2550-AC0F0A4E5800}’ n’a pas pu être installée. Code d’erreur 1642. Des informations supplémentaires sont disponibles dans le fichier journal C:\AcroRdrDC1501020056_fr_FR\log.txt.
MSI (c) (D0:48) [19:28:38:839]: Windows Installer a installé une mise à jour. Nom du produit : Adobe Acrobat Reader DC - Français. Version du produit : 15.007.20033. Langue du produit : 1036. Nom de la mise à jour : {AC76BA86-7AD7-0000-2550-AC0F0A4E5800}. Fabricant : Adobe Systems Incorporated. Réussite de l’installation ou état d’erreur : 1642.
MSI (c) (D0:48) [19:28:38:839]: Note: 1: 1708
MSI (c) (D0:48) [19:28:38:839]: Produit : Adobe Acrobat Reader DC - Français -- L’installation a échoué.
MSI (c) (D0:48) [19:28:38:839]: Windows Installer a installé le produit. Nom du produit : Adobe Acrobat Reader DC - Français. Version du produit : 15.007.20033. Langue du produit : 1036. Fabricant : Adobe Systems Incorporated. Réussite de l’installation ou état d’erreur : 1642.
MSI (c) (D0:48) [19:28:38:839]: MainEngineThread is returning 1642
=== Verbose logging stopped: 26/01/2016 19:28:38 ===