How to solve 0x80004005 error in Visual Studio while creating a Dimension Table

I'm starting from a database, let's call it D1, created by me and an empty data-warehouse. Using SSDT I'm trying to populate the dimensions of my data-warehouse from the D1. I'm doing a merge join between the source of a table of D1 and the source of the corresponding dimension table on the data-warehouse, after a conditional split to understand if it is an insert or an update and finally the insert/update. At the beginning obviously there are only insert. Now, while I'm executing the action I want to do, when the execution arrives to the insert step, it gives me the error:

Code of error SSIS DTS_E_OLEDBERROR. There is an error OLE DB. Code of error: 0x80004005.

How can I solve it?