Taking backup of all the databases in SQL Server
Note: First create a folder on D: drive. (e.g. D:\User_DataBackup\)


Step 1: Create a procedure that are given below.

Create PROCEDURE [dbo].[UserDataBaseBackUp]
AS

BEGIN
SET NOCOUNT ON;

DECLARE @name VARCHAR(50) -- database name
DECLARE @path VARCHAR(256) -- path for backup files
DECLARE @fileName VARCHAR(256) -- filename for backup
DECLARE @fileDate VARCHAR(20) -- used for file name
SET @path = 'D:\User_DataBackup\' -- as same as your created folder' 
SELECT @fileDate = CONVERT(VARCHAR(20),GETDATE(),104)
DECLARE db_cursor CURSOR FOR
  SELECT name
  FROM MASTER.dbo.sysdatabases
  WHERE name NOT IN ('master','model','msdb','tempdb','ReportServer','ReportServerTempDB')
OPEN db_cursor
FETCH NEXT FROM db_cursor INTO @name
WHILE @@FETCH_STATUS = 0
BEGIN
  SET @fileName = @path + @name + '_' + @fileDate + '.BAK'
  BACKUP DATABASE @name TO DISK = @fileName
  FETCH NEXT FROM db_cursor INTO @name
END
CLOSE db_cursor
DEALLOCATE db_cursor
END


Step 2: Execute the above procedure.

 EXEC [UserDataBaseBackUp]


You can also schedule this procedure. This procedure is tested hopefully it will help.