I have written a very simple add-in that adds a button to the ribbon of outlook (C#).
I have spent days trying to get this very simple add-in to install on another machine using the clickonce method.
I have published clickonce to ftp using Visual Studio. All fine so far.
Upon running the resulting vsto (or setup.exe) on a different machine I am getting the error:
'System.Security.SecurityException: Customized functionality in this application will not work because the certificate used to sign the deployment manifest for Add-In or its location is not trusted. Contact your administrator for further assistance.'
I understand the idea behind a certificate being required to remove rogue add-ins being added to Outlook. I have signed the clickonce deployment using a test certificate on my machine.
Simply is it possible, without paying for a third-party certificate, to give a user the clickonce url and them install it without me having to do anything to their machine? (and/or domain etc.) This is ideally to be used by lots of enterprise users. Altering their environment isn't practical.
Many thanks.
Check your certificate chain. Most likely you need to place a copy of the certificate into:
Certificates - Current User\Trusted Root Certification Authorities
...so your "issuer" is trusted in order for your certificate to be trusted.
Related
I have developed an STVO add-in for Outlook. This add-in works great on both my personal computers (Office 365) and my company computer (also Office 365).
However, an acquaintance for whom I programmed the add-in (Microsoft Professional Plus 2019) always gets the following error (error message translated into English, it may be slightly different): User-defined functions cannot be used in this application because the certificate used to sign the deployment manifest for XXX or its location is not trusted.
On all other machines I just get a warning that it could be a potential threat, but on the acquaintance's machine the above error message comes up and you can't install it.
What do I need to change so that he can install it too?
Assuming your add-in isn't signed with a trusted certificate but perhaps yours, Outlook doesn't recognize the publisher. For commercial use, it is recommended to sign the code with a "code signin certificate" issued by a trusted authority so that all customer PCs recognize the certificate. Once you have the certificate, follow these simple steps written in the documentation to sign the project How to: Sign Office solutions
I hope I have been helpful
Try to install the certificate before to running the installer - in Windows Explorer, right click on your signed file, Digital Signatures | Details | View Certificate | Install Certificate.
Before a solution can run on user computers, either you must grant trust or users must respond to a trust prompt when they install the solution. To grant trust to the solution, sign the manifests by using a certificate that identifies a known and trusted publisher. See Trust the solution by signing the application and deployment manifests.
You may find the Deploy an Office solution by using ClickOnce article helpful.
We recently updated our applications to make use of SHA-256 code-signing with a new certificate. The assemblies are strong name signed using the Sign the assembly option in Visual Studio 2015. The post build event in Visual Studio runs two signtool.exe processes to sign both in SHA-256 and for the legacy SHA-1 certificate:
call "C:\Program Files (x86)\Windows Kits\10\bin\x86\signtool.exe"
sign /f "<mystrongName.pfx>" /p "<password>" /t
<timestampURL> "$(TargetPath)"
call "C:\Program Files (x86)\Windows Kits\10\bin\x86\signtool.exe"
sign /f "<mystrongName.pfx>" /p "<password>" /fd sha256 /tr
<timestampURL> /td sha256 /as /v "$(TargetPath)"
Finally we use Advanced Installer as the installation packager and that too is code-signed on the Digital Signature page using the certificate and timestamp as per the .exe signature.
The final setup file installs and runs on Internet connected Windows machines as you would expect. You can see the certificate is assigned and valid, as well as the certificate chain through the properties of both the setup.exe and the runtime when installed. Furthermore, Windows recognizes the application as from a trusted source and displays the appropriate verified publisher details.
Our customer-base is largely global 100 companies and most of the deployments will be occurring in air-gapped networks. In one of our fist updated deployments in this environment, the certificate could not be verified preventing the installer from completing.
This made sense, because the Windows (2012 server R2) machines were isolated from the Internet and, due to company policies, had Turn off Automatic Root Certificates set to Enabled. This setting can be found in the Computer Configuration -> Administrative Templates -> System -> Internet Communication Management -> Internet Communication Settings folder of the MMC application (you need the certificates plugin installed).
When testing on our local test-bed, even machines not connected to the Internet would install the certificates from the setup utility if the above registry setting was the default (Disabled). We could replicate the issue by changing the policy setting to match the customers' (Enabled).
As a workaround, we manually downloaded the Certificate Authorities root certificate and installed it as a Trusted Root Certificate and the install would proceed normally.
When we presented this workaround to the customer, the installation still failed despite the Certificate Authorities root certificate being present in the Trusted Root Certificates of the machine.
The Certificate Authority customer service team recommended that we drop the timestamp from the signing process to allow the install to proceed - and that's the only help they offered (that's another story). However, this means that once the code-signing certificate expires, the application will either cease to run or will present unverified publisher errors.
I'm not totally convinced that this will fix the problem either, because when we tested locally the certificate was still found by the installer and allowed the installation to proceed when the Certificate Authorities root certificate was installed manually.
What I am unable to do is replicate the customers environment to exactly reproduce the problem (which doesn't help). It is almost as if Windows is bypassing the local machine's Trusted Root Certificates store. I am assuming that if this is possible it would be so that Windows can verify against a central root certificate store.
Is this even possible to set up in Windows? If so, where would I find either documentation on this or how is this done?
Am I missing something in the code-signing steps or in my understanding of what should be happening on the installing machine while it is checking the certificate?
I am at a loss as to what to do to get this installer working. What I can't afford to do is keep going back to the customer to get them to keep testing our installs. First-off it's really not the right process to debug, as the supplying vendor it isn't the customers problem to solve, but more importantly, I need our team to understand what is causing this and how to remedy it correctly.
Ideally I don't what to drop the timestamp if I don't have to because down the road this will cause new problems if the software doesn't get upgraded before the certificate expires.
Any and all help much appreciated.
I think one reason a certificate cannot be validated in an airgapped environment may be that revocation cannot be verified. As you may know, a certificate can be revoked, and there are two different protocols to check if it is, CRL and OCSP. Both require network access to the CA that issued the certificate.
Whether revocations are actually checked is governed by policies as described here, and this may cause your issues.
I made Word Add In using C# whenever I run addin, it shows following error, I enabled all macros in Trust center but it doesn' work at all.
The Deploying an Office Solution by Using ClickOnce article in MSDN states the following:
Before a solution can run on user computers, either you must grant trust or users must respond to a trust prompt when they install the solution. To grant trust to the solution, sign the manifests by using a certificate that identifies a known and trusted publisher. See Trusting the Solution by Signing the Application and Deployment Manifests.
As you may see the macro security settings of the host application does't play any role there. You need to sign the manifests by using a certificate. You can read more about that in the Configuring ClickOnce Trusted Publishers article. Also see the ClickOnce Security and Deployment section in MSDN for more information about ClickOnce installers.
I have created several applications, these are deployed on the server and will be opend by the user from the network.
Each time a user opens a application they get confronted with a security warning:
Open File - security warning
We can't verify who created this file. Are you sure you want to run this file?
Is it possible to supress this message by code?
I found an article that says I need to Sign the application but unfortunately this is not help. Another article I found says I need to manual change the security level, but that is not what I want.
I just want Windows to trust my applications.
You have to sign your application with an so called "Microsoft Authenticode Certificate". Furthermore you need to register the Certificate as Trusted Publisher on all affected machines (easy if you are in an business environment with an Active Directory).
You could use the Windows Certificate Snapin (press CTRL + R and type Certmgr.msc) to display all installed certificates on your machine. There you will find a folder named trusted puplisher. However this is only possible in business environments where you have some kind of control over the network (active directory etc.). If you're distributing your application over the internet you will have a hard time ;)
Remember, certificates are about trust and there is a reason for this warning because an *.exe file could indeed harm your computer.
EDIT:
helpful post about Microsoft Authenticode Certificates
Does anyone know how to use code signing certificate for ClickOnce manifest applications in TFS Hosted Controller Build?
Scenario:
I am using Team Foundation Service as a code repository and source control. I have created a build definition using team explorer (Visual Studio 2012).
Build "Process" using Default Template configured to Any CPU|Release
The build is set to "Manual trigger" uses Hosted Build Controller.
TFS build is unsuccessful if my project use Code Signing and Code manifests.
In my solution, two projects having "ClickOnce manifests"
Local build dont have any issues with Code signing and ClickOnce manifests - because Code signing certificate available locally for the build.
But for the same build in TFS, i get the error "Unable to find manifest signing certificate in the certificate store."
(just one error blocking the build)
Question
How can I install the code signing certificate into "TFS Build Service Account" or "Build service user account"?
How can I make the code signing certificate to avail in the virtual build machine's certificate store?
Any alternative to get clean TFS build with Code signing and ClickOnce Manifests?
Have not find the solution yet :( anyone helpful here??
Well I have managed to Sign my ClickOnce manifest in TFS auto build. My certificate was password protected and build server was not able to access the certificate because of that reason. The certificate was not in my personal certificate store hence I had the trouble.
I have imported the certificate into my local machine's personal store and from there i have referenced it for signing the clickonce manifest. When you reference the certificate from the personal store, it will not ask for the password. Hence you can cheat the TFS build and that can now access your code signing certificate..
I have a possible alternative to get a clean build for you.
My company produces a product called ClickOnceMore (www.clickoncemore.net) which can be used to build your ClickOnce manifests rather than MSBuild. It's designed to be easily integrated into a continuous integration build using a command line interface.
To integrate into your build:
* Turn off clickonce in your visual studio solution
* Create a ClickOnceMore project
* To sign the manifests you just need to put the signing certificate in a known folder location and then reference it from the ClickOnceMore project
* Add a new build step in TFS to build the ClickOnceMore project
Hope that helps.