Clearing your Office Document Cache

 Delete everything under this location

%localappdata%\Microsoft\Office\16.0\OfficeFileCache

If you wish to be neat, you can just delete all the files that begin with FS

Office Deployment Tool - Rolling out Office 365 on to clients and remote hosts

ODT is good tool if you are manual installing Office 365 applications on to clients and or remote desktop hosts.

Office 365 applications are supported on remote desktop hosts with the right Microsoft 365 license (Office 365 E3, Microsoft 365 E5, Microsoft 365 Business Premium)

Users can also manual install Office from the www.office.com portal again with the right license, but a global admin could limit this if they wish to keep office on company only devices.  If this is the case then each device needs to have Office preinstalled which can be done with ODT.

The ODT tool as can be downloaded from here or from the link in the Overview below, encase they move it and the blog is outdated.

It comes with a few options but the ones we need are download and configuration, both need an XML file

The XML file can be sorted via the Office Customization Tool found here which helps build the XML file

Overview of the Office Deployment Tool - Deploy Office | Microsoft Docs

Overview of shared computer activation for Microsoft 365 Apps - Deploy Office | Microsoft Docs

Configuration options for the Office Deployment Tool - Deploy Office | Microsoft Docs

Overview of the Office Customization Tool - Deploy Office | Microsoft Docs

A program is trying to send an e-mail message on your behalf warning in Outlook

 If you are using a Remote Desktop host and Outlook, you may come across an issue with 3rd party applications trying to send email.

Outlook will give you an warning saying that "A program is trying to send an e-mail message on your behalf"

The quick fix is to add a reg key (DWARD) setting the ObjectModelGuard to 2 as outlined in the following

https://docs.microsoft.com/en-us/outlook/troubleshoot/security/a-program-is-trying-to-send-an-email-message-on-your-behalf

The location changes based on if you have Office MSI, click to run, and 32 bit or 64 bit installed but its also in the following key

Office\<x.0>\Outlook\Security

x being the version of Outlook installed.

If this does not work you can also try the following keys in the same location

"promptsimplemapisend"=dword:00000002
"promptsimplemapinameresolve"=dword:00000002
"promptsimplemapiopenmessage"=dword:00000002
"promptoomsend"=dword:00000002
"promptoommeetingtaskrequestresponse"=dword:00000002
"promptoomaddressinformationaccess"=dword:00000002
"promptoomsaveas"=dword:00000002
"promptoomformulaaccess"=dword:00000002
"promptoomaddressbookaccess"=dword:00000002
"adminsecuritymode"=dword:00000003

But this was the older way to do it and ObjectModelGuard should be the go to at first.

Microsoft Support and Recovery Assistant

 

Microsoft Support and recovery assistant is a nice tool to help with Office applications, Microsoft 365, and Outlook issues.

Its a nice first step if you are having an issue with a device or an account.

https://support.microsoft.com/en-us/office/about-the-microsoft-support-and-recovery-assistant-e90bb691-c2a7-4697-a94f-88836856c72f

Old Access DB file corrupts over SMB for no obvious reason

 If you find your self looking at an Access database issue where it reports its corrupted randomly when it accessed over a network share.

It may be related to SMB2, if the DB was fine under SMB1 then its possibly related to one of the following settings

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters]
"FileInfoCacheLifetime"=dword:00000000
"FileNotFoundCacheLifetime"=dword:00000000
"DirectoryCacheLifetime"=dword:00000000

You will need to change this on all the clients that access the DB over SMB which can be done via GPO.

https://docs.microsoft.com/en-us/windows-server/administration/performance-tuning/role/file-server/

Downgrade Office 365 Click to Run

First you going to need to know what you are downgrading too.

https://docs.microsoft.com/en-us/officeupdates/update-history-microsoft365-apps-by-date

Once you know the build you want to use:

1. Start PowerShell Elevated
2. Type cd  "C:\Program Files\Common Files\Microsoft Shared\ClickToRun"
3. Type ".\OfficeC2RClient.exe /update user updatetoversion=16.0.<BUILD NUMBER>"

This should then trigger the Office installer which will do the rest of the work.  Once its finished I would open an office application and confirm its worked and then disable updates.

I would not recommend this as a go to fix really if you can help it.  but if you have old add-ins and plugs that are playing up on a newer build and the company is not in a position to get them updated it can help in the short term.

Long Term I would recommend resolving the issue that is that is making you downgrade and then reenable the updates again. 

Installing different versions of Office, Project, and Visio on the same computer

You can't install two products together that have the same version but use different installation technologies.

You can't install two products of different versions together if both products use Click-to-Run as the installation technology and those products have overlapping Office applications.

https://docs.microsoft.com/en-us/deployoffice/install-different-office-visio-and-project-versions-on-the-same-computer