PDF - prperties: strange problems

hello,
 
I am trying to create a PDF/A-1b: 2005 (RGB) out of a standard PDF (this standard PDF was always made out of an MS-Office document). I have 2 problems with the properties (the version I am using is not in english. hope this is the correct translation... by properties I mean the area where you can give some information about the document like: author, abstract,copyright, etc.):
 
-sometimes special letters like ö ä ü ß disappear and nonsense like %$1 appears instead. sometimes this problem can be solved by closing and reopening the document. sometimes this does not help. anyways it would not be a nice way to "solve" the problem...any suggestions for solving it for real??? what can I do so that this does not happen again?
 
-another problem: after converting from standard PDF to PDF/A-1b: 2005 (RGB) some quotation marks appeard between some of the words of the abstract. ??????? how come? what can I do so that this does not happen again?
 
Thanks for reading/thinking/answering!!!!!