In order to use the single command
SP_MSFOREACHDB "USE ?; EXEC SP_AUTOFIX_USERS;"
to sync users across all databases in 2005 instance creating SP_AUTOFIX_USERS procedure in Master database only was not sufficient.
For single command to work we had to create SP_AUTOFIX_USERS procedure in each of the user databases.
If SP_AUTOFIX_USERS was not created in particular user database the "Could not find stored procedure" error pops up.