I would have to examine your source data to see what the problem is. Maybe the attachments are orphaned on your vB forum. Or maybe there is a permission problem with the attachment file system such that some data files can't be read. Maybe some files are missing.
Try to find one specific attachment that failed to be imported. Find it on the source forum and make sure it's working there.
Are vB's attachments stored in the file system or in the database? If file system then the importer will ask you to enter the path for attachments. Make sure that path is correct and that the vB attachments exist in that directory and are readable.
If the path didn't exist then it would have given an error. So I assume the path exists but the attachments themselves do not exist or are not readable. You need to check that they exist and are readable.
i will explain you all about how i am doing the importing
vbulletin is installed on the one server and i have to install the xenforo on the another server. so i suggest to take the database and vb_attachment from the old server and upload that to new server after that i start installing xenforo to the new server and start importing all data shows importing successfully but at the time of attachments it shows import 0 attachments .
This is the all procedure if i miss any step please tell me
I have the same problem - attachments from vb3.8 are not imported. Filepath is ok, attachments are working in vb3.8 ....
Maybe they are not readable from the importer (the files are located outside the /var/www) - can I check a logfile anywhere ?
If you're sure the path is right, then this seems like the most likely cause. It's usually simplest to keep them in the same web root area, but it really varies by server setup. There isn't anything that's logged regarding the specific reason for something not to be accessed.