[Help]:( SQL Server error :'(

i change database and i restart pc now if i try login in SQL Server Group then Davio then it say= a connection could not be established to (davio) Reason the sql server the sql server do not exist or access has been refused connecttionopen (connect () (. Please verify sql server is running and verifies your sql server register properties i tryed to change pass but nothing works

Please Please Please help me :'( :'( :'( Thanks in Advance :(

what name you put in the instllation of sql, if you no change the name is (local), maybe you change only for daivo ,so you login with "davio" no "(davio)"

i have name (LOCAL) and davio