Uipath.HTml.displayactivity Custom activity - Build error

Hi @ganesh.shanmugam,

Welcome to the community.

I would like to recommend you to quickly go through this post: How to ask a good question? - News / Tutorials - UiPath Community Forum

The screenshot you posted gives little to no background on where and what activity resulted in this error.

Forum members help you much faster if you describe the scenario leading to your isssue.