powershell/sqlplus error SP2-0042: unknown command " ■@" - rest of line ignored
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I am running this command in powershell:
    sqlplus system/passwd`@mydb  `@my_sql

I have tried it with and without backticks and various other versions I found via Google. I keep getting an error when the command is passed off to sqlplus and have been unsucessful in finding the fix.  Hopefully someone here can help out?

The error I get is:
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SP2-0042: unknown command " ■@" - rest of line ignored.

So I am sucessfully connecting to the database but there is an extra character being passed to sqlplus in front of the '@'.    " ■@"  in notepad++  looks like " ¦@"