It looks like you have an error in your database connection string
The format should be like this:
<add key="MSSQLConnectionString" value="server=yourservername;UID=yourdatabaseusername;PWD=yourdatabaseuserpassword;database=yourdatabasename"/>
from the error it looks like you have extra single quotes a period or something that makes the uid seem like part of the server name.
Hope it helps,
Joe