Just happened again to me.  I got a notice that a user I know I'm not following (BOR15K) posted, but it claims I am following them.

I was re-reading the problem and discussing it outside of this thread a little bit, and I'm not sure if the current path that we are following will lead us...

heh... yep... that fixed it.  I changed my fiew to "tiles" and it was fixed so I am expecting it to be the same problem.

I'll schedule a window...

Adding to what Sue_H said, I don't think you can nicely set up a local account (such as NT Service\MSSQLSERVER) with KERBEROS without using delegation.  I think in that case...

I had this happen to me a few times too.  One time it was a spam bots post that it claimed I was following.  I still have copies of the...

Good thoughts with that Thom.  SQL Injection, while unlikely in a NVARCHAR(19), could occur.  Your solution does eliminate the risk involved of SQL injection.
I suppose if you knew that...

I could be wrong, but I think you will need to build this as dynamic SQL.  That is:
DECLARE @query varchar(255)
DECLARE @comp_cod nvarchar(19) = N'2,3'
SELECT @query...

Adding to what Sue_H said, and expanding on what Steve Jones said, I tend to avoid ms_foreachdb (for the reasons that Sue_H posted) and would much rather write my own...