Set SQL Server to automatically back up databases on a regular basis. The SQL Server Agent service is not started.

Tools and database maintenance planner in Enterprise Manager can set Regular automatic backup schedules for databases. Start the SQL Server Agent to automatically run the backup plan. The procedure is as follows:

1. Open the Enterprise Manager and click Microsoft SQL Server> SQL Server group in the root directory of the console. Double-click to open your server.
2. Click Tools in the menu above --> select Database Maintenance Scheduler
3. Next, select the data to be automatically backed up --> next, update the data optimization information. You do not need to select here --> next, check data integrity.
4. Next, specify the database maintenance plan. The default one-week backup is performed. Click "change" and select "backup every day". Click "OK ".
5. Next, specify the backup disk directory and select the specified directory. For example, you can create a directory on disk D, such as D:/databak, and then select to use this directory here, if you have a large number of databases, it is best to create a subdirectory for each database, and then select the number of days before the deletion of the backup, generally set to 4-7 days, depending on your specific backup requirements, the default backup file extension is Bak.
6. Specify the transaction log backup plan in the next step. Check whether you need to select the report to be generated in the next step. Generally, do not select the report, it is best to use the default option --> next step to complete
7. After completion, the system will probably prompt that the SQL Server Agent service is not started. First, click confirm to complete the plan settings, find the SQL green icon in the rightmost status bar of the desktop, and double-click it, select SQL Server Agent from the service list, and click the run arrow to automatically start the service when the OS is started.
8. enable SQL Server Agent Startup: run services. MSC and set SQLServerAgent to Automatic startup.

Modify plan:
Open the Enterprise Manager and click Microsoft SQL Server> SQL Server group> double-click your server> Manage> database maintenance plan in the root directory of the console.

The SQL Server Agent service cannot be started on one server.
Tip:
The SQL Server Agent service on the local computer is stopped after it is started. Some services are automatically stopped if they have nothing to do, such as "Performance Logs and alarms" service"
The log contains the following error messages:
SQLServerAgent cocould not be started (reason: unable to connect to the server "(local)"; SQLServerAgent cannot be started ).

All previous jobs can run. The service cannot be started after it is restarted.

Causes and handling of abnormal startup of SQL Server SQL Agent:

On the surface, the SQL Server Agent service is started normally, but the following error occurs when you view the job attributes and job history:
Error 14258: SQLServerAgent cannot be started. Please try again later.

Possible causes:
"Use Windows NT fiber" is selected. The specific cause is unknown.

Solution:
Enterprise Manager -- Right-click SQL instance -- properties -- Processor -- deselect "use Windows NT fiber"
Then restart the SQL service.

System Password modified
Solution:
A. My computer -- control panel -- Management Tools -- services -- Right-click MSSQLServer -- properties -- login identity -- select "Local SYSTEM account"
Or:
B. my computer -- control panel -- Administrative Tools -- service -- Right-click MSSQLServer -- properties -- login identity -- select "this account" -- select administrator, enter your administrator password in the password and Confirm Password.

Differences between the two:
Select the first method. The administrator password will be changed later. You do not need to adjust the password (but the system administrator is required to log on to the operating system)

An error occurred while the database was down.
Solution:
Use the installation CD to reinstall the registry, select 'advanced option'-'rebuild registry ', and then proceed all the way ......