Vmware Kb 55798 May 2026

Report Summary

While the article itself addresses a specific error related to STS (Security Token Service) certificate validation, its underlying principles apply to many certificate rotation or mismatch problems in vCenter Server 6.x and 7.x. Let's break down what KB 55798 covers and why it matters.

VMware KB 55798 is a classic example of the level of detail needed when working with vSphere internal security. While it solves a specific STS certificate error, the methodology—check logs, verify trust chains, restart services methodically—applies to half the certificate problems you'll ever face. Bookmark this KB, and more importantly, understand the why behind each step.

If you manage a vSphere environment, you've likely encountered certificate-related issues—whether it's a warning when connecting to the vSphere Client or a failure during service startup. One VMware Knowledge Base article that comes up often in troubleshooting these scenarios is .

VMware KB 55798 – STS certificate untrusted or expired (requires VMware account login)

Resolving SSL Certificate Errors in vCenter Server: A Look at VMware KB 55798

Accessibility Issues

These are opportunities to improve the interpretation of your content by users in different locales.

High

<html> element does not have a [lang] attribute

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

High

Form elements do not have associated labels

These items highlight common accessibility best practices.

High

[user-scalable="no"] is used in the <meta name="viewport"> element or the [maximum-scale] attribute is less than 5.

Areas of Improvement

High

Does not use HTTPS

Low

Ensure CSP is effective against XSS attacks

High

Serves images with low resolution

Search Engine Optimization Advices

To appear in search results, crawlers need access to your app.

High

Page is blocked from indexing

High

robots.txt is not valid

Make sure your pages are mobile friendly so users don’t have to pinch or zoom in order to read the content pages. [Learn more](https://developers.google.com/search/mobile-sites/).

High

Document uses legible font sizes

Language and Encoding

Language Detected

EN
Language Claimed

N/A
Encoding

UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Owa.tragsa.es can be misinterpreted by Google and other search engines. Our service has detected that English is used on the page, and neither this language nor any other was claimed in <html> or <meta> tags. Our system also found out that Owa.tragsa.es main page’s claimed encoding is utf-8. Use of this encoding format is the best practice as the main page visitors from all over the world won’t have any issues with symbol transcription.

Social Sharing Optimization

owa.tragsa.es

Open Graph description is not detected on the main page of Owa Tragsa. Lack of Open Graph description can be counter-productive for their social media presence, as such a description allows converting a website homepage (or other pages) into good-looking, rich and well-structured posts, when it is being shared on Facebook and other social media. For example, adding the following code snippet into HTML <head> tag will help to represent this web page correctly in social networks: vmware kb 55798