Sitecore Launchpad icons missing

Recently, I am working on an upgrade project (which you must have been knowing if you read few of my recent blogs) and we encountered one very weird issue on Sitecore CM.

The Issue

After successful login to CM, the Launchpad is not showing any icons.

The Solution

First obvious thing I did was open the developer toolbar and inspected the icon image requests under the network tab and it was looking like below image.

All the request to icon images were getting HTTP500 internal server errors. Also observed that .aspx extension is being added at the end of the image extension. For example, /-/icon/LaunchPadIcons/48×48/desktop.png.aspx.

Just dig around the issue, and it turned out, we recently updated the Nuget page reference for the SharpZipLib library to the latest version 1.3.3 for one of the project in customization solution.

The OOTB(vanilla) Sitecore 10.2 also uses the same library but with different version of it.

We matched the version of ICSharpCode.SharpZipLib.dll with the version number come as Vanilla Sitecore Version 1.3.2 and magically all the icons on launch page started appearing again.

Happy Sitecore upgrade…!!!