Using Sitecore 8.1
Expected Behavior
Start the installation wizard, choose/click on "Upload package" which will bring up the dialog for selecting and uploading a package file. Or if you already have the package in place, the click on "Choose package" and it will bring up the dialogue to choose the correct installation file.
Actual Behavior
Start the installation wizard, choose/click on "Upload package or Choose package" and you will see the error in a popup message window: 'The type initializer for 'Sitecore.Install.Serialization.IOUtils' threw an exception.'
Steps to Reproduce the Problem
Start the installation wizard, choose/click on "Upload package or Choose package" which presents this error in a popup message window: 'The type initializer for 'Sitecore.Install.Serialization.IOUtils' threw an exception.'
I found a blog post but the solution didn't provide the fix for me: http://bhavikmehtablog.blogspot.com/2017/09/sitecoreinstallserializationioutils_1.html It's possible that there's another dll missing or corrupt, but I haven't found it and am hoping this has already been solved. Thanks.