Issue
When trying to edit an email you are receiving the error "Cannot Load Email" with out any other details. This is only when trying to edit the email, other functionalities like cloning still work.
Solution
The reason you are receiving this error message is because the HTML of the email has been corrupted.Extract the HTML of the email by following the instructions here:https://docs.marketo.com/display/DOCS/Download+an+Email's+HTML
- Find the email and select it
- In the Email Actions Drop down click Download HTML
- Once the emails HTML is extracted you can check on the errors by pushing the HTML through a validator (https://validator.w3.org/)
**If no Errors are evident please create a support ticket.
If there are errors but you would still like to use the HTML in an email.
- Create a new email, replace the HTML with the extracted content from the old email
- Append the HTML to resolve any errors that would corrupt the content
- Save and Approve Email for use in campaigns and programs
Root Cause
Sometimes emails can become corrupted in Marketo. When this occurs unexpected behavior may occur. Typically emails become corrupted when a copy of a copy of a copy (etc.) occurs. With each clone of an asset there is a small chance that the asset could become corrupted, this becomes more and more likely as clones of clones are made.
A solution to help prevent corruption would be to create a 'master' email that you can clone from each time instead of cloning from something else that was cloned. This same solution can be applied to other assets such as landing pages.