I'm seeing a lot of this lately. I.e., statements such as:

;WITH ...

Note that the semicolon is NOT part of the WITH statement syntax. This issue only arises if the prior statement did not end with a semicolon (which it should). So the leading semicolon is terminating the prior statement.

SQL Server is starting to enforce proper statement termination. IMO, long overdue. Get into the habit of properly terminating ALL of your T-SQL statements. Even Microsoft recommends using it. From BOL:

Many code examples use a semicolon ( ; ) as a Transact-SQL statement terminator. Although the semicolon is not required, using it is considered a good practice.