@Rupert Hanna - My first suggestion would be to try duplicating the problem board and see if you can open the duplicate.

Thanks @Robert Johnson - that did the trick. Any ideas as to why this happens? The board that became unloadable had been in use for about 6 years!

@Rupert Hanna - This past week there were a number of reports of users no longer being able to open certain boards. Not working for Miro and having zero insights into the root cause, it seems like a number of boards became corrupted - so many reasons why this could have been.

If you are using a paid subscription, I would suggest opening a Miro support ticket and including the link to the affected board (you’ll may need to set the Visitors permissions for the board so that support can try to open it, but they will let you know what you need to do).

Here is how to get to the support form from a paid subscription:

https://help.miro.com/hc/en-us/articles/360020185799-How-to-contact-Miro-Support#h_01F010RXA0E1S9C0WFQYX75R6C