Expression error

Question

I was getting this error Expression evaluation error [evaluation ID = 2f483:71082] : Appian object error. Details: Failed to execute query in thread for: EntityBackedQueryExecutor [] 
 when i open a task

Harsha Sharma · Answer

I suggest you to find the process instance which has this error in the process monitoring tab. Then investigate the underlying interface if with test inputs its working fine or not. The error relates to querying data so check any variable or component that is involved in a data query to identify which one is failing and causing this error. Once you have identified the root cause then we can move towards finding ways to resolve it. So check from your end and share what you find to help us help you better!

Shubham Aware · Answer

Grant the user proper record-level security or data store permissions for whatever data the interface queries.​​​​​​​​​​​​​​​​

Mike Schmitt · Answer

I can reproduce this and I believe it is a product bug. I will be opening a support case for it later. 
 The conditions seem to be as follows: 
 1) a task is assigned and accepted, still outstanding 
 2) I, as a system admin (and presumably any other user with viewership permissions on the task instance), can open the task fine from the Process Instance Monitor, but if I try to open the task within a SAIL form via a standard task link, I get an error identical to the one you describe in your post and subsequent screenshots.

Mike Schmitt · Answer

turns out it's a product bug and is already being tracked by Appian.

Mike Schmitt · Answer

Appian Support knows of the issue and, if needed, can apply a temporary patch to your environment if it's causing you troubles - they have told me a permanent fix is either forthcoming or already deployed in newer versions (it hasn't happened to me since we originally discussed it back in late December).