the database file cannot be found. check the path to the database. data source in windows phone 7

the database file cannot be found. check the path to the database. data
source in windows phone 7

i have created the data base in windows phone 7 and it works me fine
after rebuild the application it says that
The database file cannot be found. Check the path to the database. [ Data
Source =
\Applications\Data\6157CB94-31D3-4E6F-BFC3-78BE1549C10A\Data\IsolatedStore\amit.sdf
]
my code for db string is
` private const string Con_String = @"isostore:/amit.sdf";`
how to solve this pls give me any suggestion to solve this problem