Please see below for a brief description of each of these errors. If I were to try to guess why the customer is seeing all of these, I would suspect that they are using their own scripts or tools to tamper with Chrome's installation (e.g., deleting files). Please ask them if this is the case and, if so, why they find this necessary. If they are attempting to work around a bug in Chrome's updater or uninstaller, we would certainly like to know about it so we can fix it. We can't fix what we don't know about.

I also can't help but notice that the screenshot provided shows a Chrome 65 installation, while the log messages from Google Update relate to Chrome 70 and 71.

[12/07/18 01:14:37.124][GoogleUpdate:goopdate][11008:10640][Installer failed][C:\Program Files (x86)\Google\Update\Install\{93D7E430-6266-47CF-A52F-403F08BE4027}\71.0.3578.80_70.0.3538.110_chrome_updater.exe][--verbose-logging --do-not-launch-chrome --system-level][120]

-- This is an attempt to perform a differential update from Chrome 70.0.3538.110 to Chrome 71.0.3578.80. The update failed because the file C:\Program Files (x86)\Google\Chrome\Application\70.0.3538.110\Installer\setup.exe could not be found. Is the customer taking steps to delete this file or the "Installer" directory, perhaps in an attempt to preserve disk space? If so, they should not do this, as it breaks Chrome's ability to apply differential updates and to uninstall itself, among other things.

[12/07/18 06:15:26.966][GoogleUpdate:goopdate][12128:13072][Installer failed][C:\Program Files (x86)\Google\Update\Install\{8A8B21F6-25C6-44DC-A31D-90A90CD03B42}\71.0.3578.80_chrome_installer.exe][--verbose-logging --do-not-launch-chrome --system-level][7]

-- This is a fairly generic error for an update using the full installer rather than the differential updater (likely an attempt to recover from the error above). %windir%\Temp\chrome_installer.log or %TMP%\chrome_installer.log may have more information.

[12/07/18 07:00:15.099][GoogleUpdate:goopdate][9768:13800][Installer failed][C:\Program Files (x86)\Google\Update\Install\{BD55178C-7099-480B-92B1-D9CBD50CA08E}\chrome_installer.exe][--do-not-launch-chrome --system-level /installerdata="C:\WINDOWS\TEMP\gui390C.tmp"][4]

This means that Chrome thinks a newer version is already installed. It figures this by looking at the "pv" value in the registry key HKEY_LOCAL_MACHINE\Software\Wow6432Node\Google\Update\Clients\{8A69D345-D564-463c-AFF1-A69D9E530F96}.

in the file GoogleUpdate_UK916218_20181206.log

[12/05/18 09:18:53.331][GoogleUpdate:goopdate][7040:6088][Installer failed][C:\Program Files (x86)\Google\Update\Install\{A68D345D-A362-4EC4-8141-FAAABA377AFF}\71.0.3578.80_70.0.3538.110_chrome_updater.exe][--verbose-logging --do-not-launch-chrome --system-level][50]

-- This means that the file C:\Program Files (x86)\Google\Chrome\Application\70.0.3538.110\Installer\chrome.7z could not be found. As above, is the customer taking steps to delete this file?

[12/05/18 14:20:52.171][GoogleUpdate:goopdate][6404:12428][InstallerResult][{8A69D345-D564-463C-AFF1-A69D9E530F96}][1]
[12/05/18 14:20:52.171][GoogleUpdate:goopdate][6404:12428][Installer failed][C:\Program Files (x86)\Google\Update\Install\{BB954ED8-480D-461D-A826-9E9E98EB83F1}\71.0.3578.80_chrome_installer.exe][--verbose-logging --do-not-launch-chrome --system-level][7]

-- This is a fairly generic error for an update using the full installer rather than the differential updater (likely an attempt to recover from the error above). %windir%\Temp\chrome_installer.log or %TMP%\chrome_installer.log may have more information.

[12/06/18 09:10:32.806][GoogleUpdate:goopdate][11192:5732][Installer failed][C:\Program Files (x86)\Google\Update\Install\{1BA07819-B8BE-4A70-896D-8B43A8712126}\71.0.3578.80_70.0.3538.110_chrome_updater.exe][--verbose-logging --do-not-launch-chrome --system-level][50]

-- See comment above about chrome.7z missing.

Please note that customers will not delete any kind of files from the application folder as mentioned above. 
This error comes up when an update happens. how about the possibility update itself is removing the files. 

How do we find what is causing of these files deletion. 

Chrome's installer does not delete these files.

Another possibility for error 120 is that various values in the registry have been modified. The following two commands will dump the relevant keys:

reg query HKLM\Software\Google\Update\Clients\{8A69D345-D564-463c-AFF1-A69D9E530F96} /reg:32 /s
reg query HKLM\Software\Google\Update\ClientState\{8A69D345-D564-463c-AFF1-A69D9E530F96} /reg:32 /s

It might be interesting to confirm that setup.exe and chrome.7z are present (replace "W.X.Y.Z" with the actual version installed):

dir "C:\Program Files (x86)\Google\Chrome\Application\W.X.Y.Z\Installer"

As far as how you might find out what has deleted these files goes, I don't have much to offer. Process Monitor can be used to monitor all filesystem activity, but I don't imagine it's practical to run it all the time.

Do these Chrome installs originate from the Chrome .MSI installer? Is it modified in any way? Does the customer use custom deployment scripts that do something before/after installing/updating Chrome?

It might be interesting to confirm that setup.exe and chrome.7z are present (replace "W.X.Y.Z" with the actual version installed):

dir "C:\Program Files (x86)\Google\Chrome\Application\W.X.Y.Z\Installer"

I did a check on the above part and I can confirm that these files are present with the actual version installed.

Process monitor cannot be ran all time on the machine considering the large environment we have. This might lead to other issues. 

This error is appearing when chrome is updated to eg(70 to 71), where 70 was working fine and upgrade worked when it updated to 69 to 70. 

As you mentioned above, if these files are getting deleted, we would need to find the cause, Appreciate your advice. 

Note that we have been investigating this from more than an year and we are no where with this. 

Another issue here is once the update failed and error popped up, we cannot uninstall Google chrome. It gives error stating files are missing.

Hi. This sounds like a very interesting mystery. Could you provide some more background on your ordinary Chrome install+update procedures? In particular:

- Which type of Chrome installer do you use for your initial install (i.e., the Google-provided .msi installer, the Google-provided "standalone" .exe installer, or other)?
- Do you make any local modifications or customizations to the above installer (e.g., editing the MSI, wrapping it in another installer, etc)? If yes, please explain.
- How do you run the above installer?
- Do you take any steps to disable Google Update? If yes, please explain.
- How do you deploy updates?
- Do you attempt to uninstall prior versions of Chrome before installing an update? If yes, please explain why.
- What security software do you have running on the impacted machines?
- Is it possible for you to periodically survey the impacted machines to see if files within C:\Program Files (x86)\Google\Chrome\Application are vanishing?

If possible, please provide C:\Windows\Temp\chrome_installer.log from the machine(s) that failed to update on 12/05/18 14:20:52.171 and 12/07/18 06:15:26.966.

grt@ Please find the Answers below :

- Which type of Chrome installer do you use for your initial install  (i.e., the Google-provided .msi installer, the Google-provided  "standalone" .exe installer, or other)? 
the Google-provided .msi 

- Do you make any local modifications or customizations to the above installer (e.g., editing the MSI, wrapping it in another installer, etc)? If yes, please explain. 
We don't make any changes to the MSI file.. But we do _CUSTOMER_ standards to an MST. 

- How do you run the above installer? 
Google Chrome is part of our image only /Reinstallation will be done via SCCM 

- Do you take any steps to disable Google Update? If yes, please explain. 
No We don't 

- How do you deploy updates? 
Its via google updater only. Whenever googles releases the update, chrome updates automatically. 

- Do you attempt to uninstall prior versions of Chrome before installing an update? If yes, please explain why. 
Update is happening via Chrome updater, we don't manually update it. 

- What security software do you have running on the impacted machines? 
We have Avecto, Qualys , Cylance , Tanium ,Bluecoat ,windows defender and Digital guardian. 

- Is it possible for you to periodically survey the impacted machines to see if files within C:\Program Files (x86)\Google\Chrome\Application are vanishing? 
The issue happens randomly on any machines. We will be reinstalling chrome to fix the issue, Its not mandatory that the issue will appear again on the same machine on next update. 

- If possible, please provide C:\Windows\Temp\chrome_installer.log from the machine(s) that failed to update on 12/05/18 14:20:52.171 and 12/07/18 06:15:26.966.
Attached chrome_installer_UK913288.log https://drive.google.com/open?id=1wEYN9NLIiWQGBMVuNY2h4rBk67NeV_d-

Could you check with the various piece of AV software you're using to see if any of them are moving chrome.7z into a quarantine directory? My guess is that this is what's happening.

I took a look at the log. It's from a different install run than the others, so I can't say that it's showing the same problem. It indicates a failure to update because pre-existing files for the same version being installed (71.0.3578.98) cannot be moved out of the way:

[1218/140348.761:ERROR:move_tree_work_item.cc(82)] failed moving C:\Program Files (x86)\Google\Chrome\Application\71.0.3578.98 to C:\Program Files (x86)\Google\Chrome\Temp\scoped_dir14204_15484\71.0.3578.98: The process cannot access the file because it is being used by another process. (0x20)

This could happen because that version of Chrome is running, or because A/V software is doing work in that directory and preventing it from being moved. Did that machine already have 71.0.3578.98 installed? The subsequent installs fail because an installer for an older version of Chrome is being used.

What do you see in the "pv" value of that machine's HKLM\Software\Wow6432Node\Google\Update\Clients\{8A69D345-D564-463c-AFF1-A69D9E530F96} key?

We do not have the above machine anymore with US. Hence its affecting users, we had to reinstall and resolve the issue. 

Could you help us to narrow it down to see what security product is causing the issue. If the issue is files getting removed from C:\Program Files (x86)\Google\Chrome\Application\W.X.Y.Z\Installer", in which log we can identify which product is causing issue?

Initially we have given couple of logs, just curious to know if its the same file getting deleted 

Based on the log messages from the initial report, setup.exe and chrome.7z vanished from C:\Program Files (x86)\Google\Chrome\Application\70.0.3538.110\Installer. I'm not sure if these two failures were on the same machine or on different machines. I'm afraid I don't have any detailed knowledge about the various pieces of security software you are using. I would expect that such security software has a way of logging its activity, either in the Windows Event log, or in some centralize log facility.

If the initial install is done via the Chrome MSI and updates are applied by Google Update, then I'm surprised that these machines don't eventually update. If setup.exe and/or chrome.7z disappears, I would expect that the first update attempt would fail (the one using the small differential updater) and that the second would succeed (this one would be the full Chrome installer).

It's possible that you can eliminate the first failure if you can figure out why these files are disappearing and make that stop.

It's possible that the second failure would happen in either case. Perhaps we should focus our efforts on this second failure.

Is it the sudden "side by side configuration" error that alerts you to a machine with a problem? The next time this happens, could you zip up C:\Program Files (x86)\Google\Chrome\Application and include both C:\Windows\Temp\chrome_installer.log and the user's %TEMP%\chrome_installer.log (if there is one)?