I'm having the same problem trying to install vCenter Server 6.0 Linux-based appliance.  I see it's only been a few days but am hoping by replying I might kick start this post and get an answer to the problem.

To reiterate, trying to deploy vCenter Server Appliance by mounting the ISO and launching vcsa-setup.html in the root of the disk's file system.  I had to install the Client Integration Plugin (no issues noted), and then when I launch vcsa-setup.html I eventually get the exact same error:  Restart Firefox, but I am not even using Firefox.

Every time the Client Integration Plugin popup appears click OK to dismiss it.

When the installation of vCSA 6.0 completes, uninstall the VMware Client Integration Plugin 6.0.

You don't really need it to open the vSphere Web Client in your browser.

You have to add vCenter's FQDN address to "Local intranet" zone in Security settings of Internet Explorer 11.

Answered in Sphere Web Client integration plugin problems in Windows 8.1

Thank you Trakatelis

adding the URL to IE security settings worked for me.

Thanks, this worked for me as well.

Thanks trakatelis, adding the URL to the IE security settings, worked for me, in IE and Chrome.

Regards.

It worked for me as well.

Thanks for all posts. 

I had been using FireFox, but there is some functionality that is not working/available in FireFox. I spoke with a VMware engineer at a VMUG and he stated to use either Chrome preferably or IE11. Company policy doesn’t allow Chrome.

I started receiving this message after running Windows Updates on 10 Enterprise when opening IE11. I had been using IE11 for weeks without issue.

I added the FQDN to the Local Intranet zone in IE11, but was still receiving the message. I followed the link in trakatelis’s post. https://communities.vmware.com/thread/462312

On this Discussion, I followed ericmowatt and BKNZC’s suggestions with these changes.

Uninstalled the Client Integration tools from Program and Features

Browsed to the VMware folder and removed all residuals from the Client Integration tools installation. Be sure to check the parent folder before uninstalling to be sure you don’t delete other VMware software installation files.

Restarted the pc.

Right clicked the installer and ran as admin. Originally I had saved the Client Integration tools installer versus running it.

Right clicked IE11 and ran as admin. Then checked to be sure the FQDN was still in Local Intranet zone.

Went to the vCenter server URL and logged in. All functionality is there.

I had used FireFox again since it’s my browser of choice to do some quick tasks in vCenter. The next time I used IE11 I received the above message again. So, I went back through the steps again and now IE11 is working without the message and all functionality is back.

It appears in my case, IE11 and FireFox have an issue. I still use FireFox most of the time and IE11 has not had any issues with vCenter since I’ve not accessed vCenter with FireFox.

vCenter Server 6.0 U2 on server 2012 R2 ver 6.3.9600  

vSphere 6.0 U2

IE11 11.321.14393.0 on Windows 10 Enterprise ver 10.0.14393

FireFox ESR 45.4.0

OP may have long since resolved this, but just to add a different solution to this, I was having the exact same issue - only use Chrome and IE11 but getting the Firefox popup - it turns out the client integration plugin assumes you have Firefox installed if it finds an old Mozilla Firefox profile hiding within your %AppData% profile folders (presume they don't check for properly installed versions incase people run portable Firefox perhaps? ).

You can verify this by inspecting the csd.log files (usually kept within AppData\Local\VMware\CIP\ui\sessions\*)... I had entries like these...

[2017-01-03 09:18:50] [INFO] Registering certificate for FireFox

[2017-01-03 09:18:50] [INFO] Process [Ag5N-X38F-OXcw-1n6Q]: Starting [sync] certutil

[2017-01-03 09:18:50] [INFO] Process [Ag5N-X38F-OXcw-1n6Q]: Process created: certutil -A -n vmware-localhost -t TC,, -i C:\ProgramData\VMware\CIP\csd\ssl\cert.pem -d C:\Users\XXX\AppData\Roaming\Mozilla\Firefox\Profiles\p9zy32qx.default

[2017-01-03 09:18:51] [INFO] Process [Ag5N-X38F-OXcw-1n6Q]: Process with ID: QyUT-UDyA-Okks-RXbt has terminated.

[2017-01-03 09:18:51] [INFO] Process [Ag5N-X38F-OXcw-1n6Q]: Output...

[2017-01-03 09:18:51] [WARN] Failed to register Firefox certificate.

So this failed because Firefox had been uninstalled but left the profile folder in place - my solution was simply to delete the old Firefox profiles from AppData\*\Mozilla\Firefox\Profiles

I had a tough one today, and all the normal fixes didn't work until I found an abnormal one.   Finally resolved, check it out (also, sorry for the lack of links but I'm sure you have seen all the posts that suggest these steps already):

• VMware client integration plugin on Firefox 52.0.1 - CIP version 4911605 - vCenter 6.0 latest version (U3)
• When connecting to WebClient, after installing the plugin, the same issue occurs again - prompt to install plugin and cannot use Windows session credentials.  Then popup saying Firefox has updated its SSL cert.
• Setting RSA / AES to false in Firefox - no change
• Run CIP as Administrator - no change
• Tried to import CA certificate but gives the error "This certificate is installed already"
• Set Firefox to use proxy setting, both auto and straight use - no change
• reloaded the certificate - no change
• changed Windows hosts files - no change
• Deleted hosts.bak file - no change
• Removed Read-only flag on hosts file - no change
• FQDN is added to trusted sites, local intranet - no change
• about:config > dom.ipc.plugins.asyncInit = false - no change
• Complete reinstall and file deletion - no change. Although we did import favorites.
• Found a workaround download of the CIP but it was only 8MB compared to the 94 MB of the other one and also would not run.

Finally did this:

• Removed the Firefox profile folder completely and then reinstalled and imported no settings - "could not open Firefox due to missing profile"
• RENAMED the profile.ini file in App/Data/Mozilla/Firefox to profile.old and Firefox generated a new profile.
• Reloaded the Web Client page and it prompted to use the CIP - imported the Certificate and the CIP is now working.

Thanks for posting, it's working well for me.
บาคาร่าออนไลน์

A good question Thanks for the reply.

Gclub

hi all,

I'm using w2k12r2 + Firefox v53.0.3 x64 and this problem also hit me... heeh

This WebClient starting to be not only terrible VMware management mistake and wasting of our time but also starting to be really close to impossible to manage VMware vSphere environment, and in any disaster recovery we may be sure to have no possibility to manage it fast because of such "interesting" problems...:((

The solution to add FQDN and IP address to IE Trusted zones also works for me, so for W2k12r2 + Firefox v53 x64, VMware vSphere v6.0U3, really awesome!!!

thanks mates.

kind regards

NTShad0w

It worked for me, Thanks.