Fix for this issue is now available in the latest update of InDesign 2020 – that is, InDesign 15.0.1
In the Creative Cloud Desktop application, click on the Updates section on the left. You should be able to see the Update available for InDesign. Please update your InDesign application to this version to try out the fix.
Let us know in the comments section if you face any problem with the updation process.
Adobe InDesign TeamJoshua Marner commented
This constantly happens for me. Sometimes it hangs at 5% for a large export (100MB+ PDF export) and doesn't write anything, and other times it hangs at 99% for a normal export (10MB+ PDF export) but the exported file seems to be complete.Joshua Marner supported this idea ·