I solved the issue as I configured the account on an Outlook for MAC, copied the pst with the mails from local failure folder to the MAC and import them there to Exchange and it works perfectly.
Thanks for your answer.
Ok - I thought local failuers are only locally not in the ost.
I tried to open the pst file and to drag them to a folder in the mailbox but it doesn't work.
I also tried to import them to another account and I also tried to repair the pst file - nothing helps...
Local failures files are not in the ost the are only local - therefore the name.
I try to create a folder unter Inbox and tried to drag mails from local failures to the new folder but the always will be moved again to local failures folder.
Thats my problem.
I configured an Outlook 2010 client for using an exchange account and want to import an previously exported pst file.
The most mails were imported without problems but for a few mails I get an synchronisation error and the mails will be moved to the "Locale failures" Folder.