[FIXED] (B1900.8) Cannot open scenario: "Object reference not set to an instance of an object"

[oiajz]

Upon trying to open a scenario which I have been working on, my computer freezes for maybe half a second and the below error appears. I know the devs prefer clean scenarios for bug reporting but I have had this happen before, maybe a year ago, and both times I have had between 1500-3000 units, so maybe it is linked to that? Either way I have no idea what caused it so this is the best that I can offer. I have included the exception log as well.

Screenshot 2026-08-27 232752.png (14.63 KiB) Viewed 361 times

[Raptorx7_slith]

Thanks, logged as 0017585

[Nikel]

Similar or the same xml errors than in this previous report.

https://forums.matrixgames.com/viewtopi ... 7#p5281837

[Deserere]

hi oiajz
the issue was caused by a corruption in the scenario file (pretty random I think) and a field that was not sanitized correctly before serialization.

A fix for the sanitization will be included in the next update release.
In the meantime I manually recovered your scenario.
Attached the file, you should be able to open it now.

[oiajz]

Thank you for fixing it, much appreciated!

[oiajz]

I have had the same issue happen again with the same scenario after it was manually fixed, what can be done? I feel like requesting it to be recovered again is asking too much of the devs but at the same time I have spent too long on this to just throw it away.

[Deserere]

Wait for the new update release so that the issue will not happen again before continue working on your scenario, saving with your current version can break this specific scenario.
As an extra test I opened it with my version of CMO, just opening it and then save it fixes the issue.

Attached

[oiajz]

Thank you so much, sorry to have been a pain. I will wait for the update as you suggested before messing around with it again.