Versions (Be specific, do not write "latest"):

• Polymorph: polymorph-forge-1.16.5-0.27.jar
• Forge/Fabric: forge 36.2.9

Observed Behavior: Server crashing while we updated the mod's version

Expected Behavior: Not crashing?

Steps to Reproduce:

Update polymorph.

Crash Log: Please use a paste site like hastebin.
https://pastebin.com/PR6FBHQ8

Having the same issue after updating to the latest version of Polymorph. Server starts up fine and then just hangs to the point that the player numbers when pinging the server responds with ??? and then just causes the server to shut down due to hanging.

UPDATE: 0.25 works fine. 0.26 and 0.27 have the same issue.

I can't reproduce this issue, so it might take some time for me to figure out what's going on. I have some idea, because this happened during testing at some point before I implemented a solution, but I'm not sure why it would still be happening.

Current workaround: Disable the Refined Storage integration by going to your config folder, locating polymorph-integrations.toml and set refinedstorage = false. This will disable the integration and probably let you load your world at least.

Ok thankyou, not sure if it helps but when the server crashed it did generate a crash report, not sure if its identical to the OP, but always good to have multiple crash reports.
https://pastebin.com/Zi1u4tJs

Alright, I'll need some help from you two since you're encountering the error and I'm not. Can you use this test build of Polymorph with Refined Storage and see if it fixes the issue:
polymorph-forge-1.16.5-0.28-SNAPSHOT20211107.zip

Make sure to re-enable the integration in the config if you disabled it as mentioned in my previous comment.

I'll add it in now and test it

Pleased to report it is now working. No crashes when I log in.
Servers been running stable for 5 minutes now.