How to change the flatfile connection manager "file name" value in SSIS package?

Question

I have an ssis package...which read data from fixed-column-width text file into DB table.

And I am modifying an existing ssis package. I have a flat file source...and flat file cnnection. When I try to edit the flat file connection...using "flat file connection manager editor"..., under "general" part...even if I select different filename..it's not getting reflected.

OR...select the properties window of "Flat File Connection" - once I change connection string and click "save" of visual studio...it rollback

Help me please.

Answer 1

Pulling a useful comment into an answer...

It's possible that that Connection string (the file path, name) is set from an expression/user or project parameter.

To check, right-click the flat-file connection manager and go to Properties, then check Expressions to see if the ConnectionString is set from a variable such as @[User::MyFileConnectionString]

That would cause this behavior of it seemingly "un-doing" after you change it manually.