Unable to update embedded Git

I'm unable to update the embedded Git client from version 2.11.0 to 2.12.2.2.

This is the error message I'm getting:

7-Zip [32] 16.02 : Copyright (c) 1999-2016 Igor Pavlov : 2016-05-21

Scanning the drive for archives:
1 file, 35052200 bytes (34 MiB)

Extracting archive: C:\Users\myuser\AppData\Local\Atlassian\SourceTree\PortableGit.7z
WARNING:
C:\Users\myuser\AppData\Local\Atlassian\SourceTree\PortableGit.7z
Can not open the file as [7z] archive
The file is open as [PE] archive

–
Path = C:\Users\myuser\AppData\Local\Atlassian\SourceTree\PortableGit.7z
Open WARNING: Can not open the file as [7z] archive
Type = PE
Physical Size = 35052200
CPU = x86
Characteristics = Executable 32-bit
Created = 2017-03-28 15:36:45
Headers Size = 1024
Checksum = 35099190
Name = 7zS.sfx.exe
Image Size = 217088
Section Alignment = 4096
File Alignment = 512
Code Size = 141312
Initialized Data Size = 61440
Uninitialized Data Size = 0
Linker Version = 14.10
OS Version = 6.0
Image Version = 0.0
Subsystem Version = 6.0
Subsystem = Windows GUI
DLL Characteristics = Relocated NX-Compatible TerminalServerAware
Stack Reserve = 1048576
Stack Commit = 4096
Heap Reserve = 1048576
Heap Commit = 4096
Image Base = 4194304
Comment = FileVersion: 16.4.0.0
FileVersion: 16.04
ProductVersion: 16.4.0.0
ProductVersion: 16.04
CompanyName: Igor Pavlov
FileDescription: 7z Setup SFX
InternalName: 7zS.sfx
LegalCopyright: Copyright (c) 1999-2016 Igor Pavlov
OriginalFilename: 7zS.sfx.exe
ProductName: 7-Zip

Path = [0]
Size = 34847168
Packed Size = 34847168
Virtual Size = 34847168
Offset = 194048
–
Path = [0]
Type = 7z
Offset = 515
Physical Size = 34846646
Tail Size = 7
Headers Size = 61570
Method = LZMA:27 BCJ2
Solid = +
Blocks = 2

Sub items Errors: 1

Archives with Errors: 1

Sub items Errors: 1