Your HTML looks solid to me and renders properly in Chrome and IE 9. The problem you are running into is on the email client side (Outlook and/or gmail) and...

This blog post illustrates one big difference: SQL Server: JOIN vs IN vs EXISTS - the logical difference

Right now, you are only replacing the Cr, CrLf is CHAR(13) + CHAR(10).

Is the rest of the email displayed using the expected HTML formatting? Can you view the source...

Did a little more digging, and although I've never used it, it may be SCCM that needs this account and you are likely having some AD/trust issue. Sorry I can't...

I think you are looking for the RowNumber Function in SSRS: http://msdn.microsoft.com/en-us/library/ms159225.aspx

What process is running that needs access to the server? It must be something.

The server itself shouldn't need access to SQL. They are likely running a process (Windows Service, ASP.NET, etc) on that application server, and the user the process is running under...

You've got at least one copy/paste error in there:

and year(manufacturing_end_time) > @month

Are you doing this in the detail section by any chance? If so, the count is one (for each row).

The only thing I would add is that you might be looking for RANK or DENSE_RANK instead of ROW_NUMBER, depending on the specs.

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