# Property size mismatch **URL:** \ **Category:** Platform & Builds\ **Tags:** unreal-engine, bug-report, question\ **Created:** [March 21, 2016, 8:46pm UTC](https://forums.unrealengine.com/t/property-size-mismatch/351282 "2016-03-21T20:46:35Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![anonymous\_user\_2b03d27c](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_2b03d27c](https://forums.unrealengine.com/u/anonymous_user_2b03d27c)\ **Post date:** [March 22, 2016, 2:08pm UTC](https://forums.unrealengine.com/t/property-size-mismatch/351282/2 "2016-03-22T14:08:40Z")
hey - I want to confirm if it is intentional that you created a class based on actor and then changed it to inherit from UInterface? I’m also not sure how you’re adding the class to the level after your changes since after the changes the class is an interface rather than an actor which cannot be placed in the level. If you are trying to use an interface in code, it may help to the tutorial for interfaces that was created by another community member: > **[A new, community-hosted Unreal Engine Wiki](https://forums.unrealengine.com/t/a-new-community-hosted-unreal-engine-wiki/141494)** > > After over a year in maintenance mode, the official Unreal Engine Wiki is now permanently offline. These resources now live on a new community-run Unreal Engine Community Wiki — https://unrealcommunity.wiki/! You will be able to find content from... Cheers --- _[View the full topic](https://forums.unrealengine.com/t/property-size-mismatch/351282)._