Database backup issue in SQL Server For security reason I always took back up of my database. I took full backup in each month. And differential in each week. I used to save each back up file in different name. I lost my latest full back up file. But I have my latest differential back up file. So when I tried to restore my differential back up with the previous full back up , I am getting an error that 


  This differential backup cannot be restored because the database has not been restored to the correct earlier state


My scenario:


Took Full Backup        - File is with me
Took Differential       - File is with me
Took Another full       - Lost this file
Differential file       - is with me


So can I restore 4th one with 1st one. With out the 3rd ?

Is there any solution for this scenario? Can I restore it without losing data? 

I am using SQL Server 2008 R2
Since you said you are beginner and is in learning phase I would give you lot of good articles to learn about SQL Server backup.

To start with main question as already mentioned in my comment


  So can I restore 4th one with 1st one. With out the 3rd ?


Differential backup only relates to previous full backup you have taken so NO you cannot restore 4th differential backup if 3rd full backup is lost. Also since as you said the database is in simple recovery model there is no chance of taking transaction log backup.


  [To understand] Whether there any way if it is not simple ?


If your database were in full recovery you could have taken Transaction log backup. The good thing with transaction log backup is that Minimally, you must have created at least one full backup before you can create any log backups. After that, the transaction log can be backed up at any time unless the log is already being backed up. 

So you could have restored first full backup and all log backups, in serial order, taken after the full backup. This would hold true even if 3rd full backup is lost.

You must read Understanding Backups in SQL Server there is a Backup myth buster series from PR related to backups you must also read that.

Feel free to ask if any doubts I would add the comments in this answer