Marketpath CMS provides the ability to replace images and documents with a different version. When doing this, the original image or document name will be retained which may, in turn, have an impact on your ability to view the newly uploaded file. Images and documents are affected by various caching mechanisms throughout the network - from your browser client to the actual physically stored file. 

Caching is essentially a method of storing objects that enables faster downloads and a better user experience. For example, the first time you visit a company's website the company logo is loaded (among other files) and stored in your computer's local memory. The next time you visit the site, or if you click through to another page that also has that logo, your browser will not have to download it again. It quickly loads it from local memory creating a much faster load time for that page.

The three primary caching mechanisms are described below with examples of how you can clear the cache.

Browser Caching

As described above, your browser will cache resources (i.e. save them to your local disk) when you load a website. It will cache images, documents, style sheets, and any script files that are referenced. As you browse through a website, most of its pages will likely use the same style sheets and script files and many of the same images. Rather than downloading those again, your browser will load them from your hard disk or memory significantly improving the total load time of the page.

Usually, to force your browser to download content again you can perform simple keystrokes and/or mouse clicks. These vary depending on your operating system and browser. Here is a resource that should help you find yours:

https://en.wikipedia.org/wiki/Wikipedia:Bypass_your_cache

If you want to clear the cache so your browser is forced to download those resources again you'll need to refer to your browsers documentation or visit an external site to learn how. Because this changes we will not cover it here. But here are a couple resources that should help:

https://www.wikihow.com/Clear-Your-Browser%27s-Cache

http://www.refreshyourcache.com/en/home/

https://kb.iu.edu/d/ahic

Content Delivery Network Caching (CDN)

A content delivery network, or CDN, is a special network of servers that delivers content quickly, typically directing you to the closest physical server or to servers with the least amount of traffic. CDN's optimize content delivery by pulling from a primary source and replicating to each edge node server. One image may be replicated in 10 or 15 different locations around the world. Marketpath CMS uses Microsoft Azure CDN.

When you replace an image or document, we send a request to Microsoft Azure CDN to purge the content. It may take several minutes to replace content from every edge node. These servers are high load, high traffic servers that can deliver millions of pieces of content every minute. They are optimized for delivering content, not managing content.

Once you've replaced an image or document, the replacement should be available after 3-5 minutes. This could take longer depending on the traffic load of each edge node. Unfortunately, there really isn't anything you can do to make this faster.

Proxy Servers

Your company or organization may have a proxy server setup that also provides resource caching. This helps an organization's network reduce downloads by caching the resources. If 1 or 2 people are visiting the same site, it won't have much of an impact. But if 100 or 1,000 people are visiting the same site, it can have a tremendous impact on the company's Internet download speeds. 

If you're experiencing issues with organizational caching, then you should contact your Information Technology team to assist. They are likely the ones with the keys to clear the cache on a proxy server. Before you do this, however, we recommend you clear your browser's cache first and wait a few minutes for changes to take effect across the CDN.