Refresh fails after appending to working data sources - any reason why?

[Anonymous]

I have gone back to scratch and added a data source and created a basic table, all good. I added a second and repeated the steps still all good including a refresh.

However, as soon as I append the two data sources and then do a refresh it fails on the newly appended data. Is anyone able to offer an explanation as to why two sets of data work fine but when appended they cause a fail?

Thanks in advance.

S

[amitchandak]

@Anonymous , What is the error it is giving.

one of the append sources is having incremental and another one not having can also cause that

[Anonymous]

Apologies for delay was on leave. The error produced is

Failure details: The last refresh attempt failed because of an internal service error. This is usually a transient issue. If you try again later and still see this message, contact support.

Information is needed in order to combine data;Information about a data source is required.. The exception was raised by the IDbCommand interface. Table: Append1

Thanks.