Error en un plan de mantenimiento

Hola,

Tengo un plan de mantenimiento el cual realiza un proceso de integración,
una optimización y un backup de la bbdd Master y otra BBDD.

Viendo los logs nos aparece el siguiente error:


Microsoft (R) SQLMaint Utility (Unicode), Version Logged on to SQL Server
'SERVER\SERVER_01' as 'NT AUTHORITY\SYSTEM' (trusted)
[Microsoft SQL-DMO (ODBC SQLState: 42000)] Error 5105: [Microsoft][ODBC
SQL Server Driver][SQL Server]Device activation error. The physical file
name 'D:\Program Files\Microsoft SQL
Server\MSSQL$SERVER_01\Data\BBDD_Data.mdf' may be incorrect.


2005-06-22 01:00:00.79 spid54 udopen: Operating system error 32(The
process cannot access the file because it is being used by another
process.) during the creation/opening of physical device D:\Program
Files\Microsoft SQL Server\MSSQL$SERVER_01\Data\BBDD_Data.mdf.

2005-06-22 01:00:00.79 spid54 FCB::Open failed: Could not open device
D:\Program Files\Microsoft SQL Server\MSSQL$SERVER_01\Data\BBDD_Data.mdf
for virtual device number (VDN) 1.

2005-06-22 08:43:30.20 spid3 SQL Server is terminating due to 'stop'
request from Service Control Manager.


¿Alguien me podria indicar cual es la solución?

Saludos y gracias