Getting error message on deleting a file:

Hello
Getting error message on deleting a file:
.net 3.5 c#
I got 2 issues
[1]
Error Deleting a file MSG:
 
System.IO.IOException: The process cannot access the file '281px-Phangan_Map3.jpg' because it is being used by another process. at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) at System.IO.FileInfo.Delete() at UtilsIO.DeleteAllFilesOnDir(String sDirPath) in c:\Users\y\Documents\code\Bongalows\App_Code\BL\Utile\UtilsIO.cs:line 40
 
[2]
I am trying to exec the from a <a href"xx.aspx" target="_blank">delete
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Issue no1:
Cant delete the files after use them - so need to find a way to close the life service or something
Issue no2:
When  I am trying to delete the file from a new link target ...