Hello! I am very sorry if this thread is in a wrong place or just too stupid, but I have nowhere else to ask. I ask them in one thread to not to make too many threads. Undelivered Mail Returned to Sender This is the mail system at host ******. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to postmaster. I was trying to send an email, but it was sent back quite some times. A traffic jam?! Somebody has had encountered similar problem? And I would like to ask about disk checking. My Computer-Local Drive C:-Right Click-Properties-Tools-Error Checking. It doesn't work anymore. If I mark both Automatically fix file system errors and Scan for and attempt recovery of bad sectors it won't start at all. When I only mark Scan for and attempt recovery of bad sectors then two phases are done and message about not being able to complete the process appears.