An unhandled fault has occurred in this flow An unhandled fault has occurred while processing the flow. Please contact your system administrator for more information.

このヘルプを読んでもよく分からん。

Lookup field in flow throws error: 'An unhandled fault has occurred in this flow'

未解決

• Problem in Custom Metadata Types Basics module submodule Use Custom Metadata Types in Flows

解決か？

必須フィールドに値がセットされていない。

• フローのエラー：このフローで未処理の障害が発生しました
• フローの処理中に未処理の障害が発生しました。詳細については、システム管理者に問い合わせてください。

I used Custom Metadata Types (CMDT) to automate fields updates and populate some field values. It works fine in the DEV1 org, but when I deployed the Flows and CMDT to DEV2, I am getting an 'UNKNOWN_EXCEPTION: An unexpected error occurred. Please include this error Id if you contact support: 1864777442-209431 (1156755792)'. No other information.

• UNKNOW_EXCEPTION: An unexpected error occurred...

I finally was able to isolate the issue. For everyone's knowledge, I will explain.

There was an existing Subflow, that was triggered by Process Builder before. We converted those Process Builders, in to a combined Record Triggered Flow, and the subflow was also included. The subflow was set to run 'System Context with Share - Record Level Access Enforced' which unfortunately a Record Triggered flow cannot trigger! I have changed the context to 'User or System Context - Depends on How the Flow is Triggered' and that resolved the issue.