Today, I came across a very strange error, for some reason when I navigate to SharePointSite/SitePages/ and try to create a new Web Part Page, I get the following error.
This was quite strange, as it used to work perfectly regardless which browser I was using.
I tried couple of things:
- Try different browsers
- Clean the cache and restart the process
- Logout of Office 365 and log in again
None of these seemed to work, so I tried one last thing, which was switching to the Classic UI.
Apparently, for some weird reasons, I was not able to create web part pages in the modern UI.