Local Database after have SQL express installed

I have Samba installed in my computer with SQL express. Now I only need use one computer so I erase everything and install samba again but this time compact edition.
When I open my new samba installation the screen Connection String appear saying: Can’t connect to the database with current setting you can check or…

My question is Why this warning appear if I jusyt install a compact edition no the server one?

Thanks in advance

No don’t use compact edition. It does not support some extended indexing features so reports may work slower as database size increases. Unlike V3 we install SQL Server Local DB by default with V4. I strongly recommend keep using SQL Express.

PS: While asking a reason of an error please add some screenshots or give more details about your current related configuration so we can understand what it wrong.

Ok Thanks Emre I will try to by more specific.

I connect 3 computer in network to test the software working together and the result was excellent. Beautiful program. Now I will sale a POS system to one of my customer but at this time with the SambaPOS software installed (only one terminal).
Because will not need in the future more terminal (to small business) I uninstall the program with multi user mode deleted SQL express and all relative to samba them install fresh copy of Samba but selecting local database. When finish the installation , open samba for fist time and this is what appear:

and this area suppose to be empty, after this; erase “Data source= …” leave the space in blank, save and close the program, open again and the same warning appear again with the same info that I erase before . When I install this time. I don’t config the nothing in “local setting/data connection string
How can just connect to the samba program normally again without this warning and without this connection string?

Thanks in advance.

Try clearing everything and just typing a single space.

Thanks Emre very Thanks