Cannot consistently drag and drop .msg files into Outlook 2010

Question

I have a large set of .msg files created by another user, which I need to import into my Outlook. The majority load normally. Some (around 5%) fail with the message:

Cannot copy the items. Cannot open file : < file >. The file may not exist, you may not have permission to open it, or it may be open in another program. Right click the folder that contains the file and then click Properties to check your permissions for the folder.

I can open every offending .msg file from explorer by double clicking it, even if I can't drag it into outlook. There appears to some sort of lock on those files but I don't how to tell Outlook to load them anyway.

I have tried:

• Outlook in safe mode
• Outlook with all add-ins disabled

Answer 1

I just responded to your question with a comment that I had the same problem and couldn't figure it out. I managed to fix it, and in retrospect quite easily.

I was trying to drag and drop about 500 .msg files from a folder on my drive to my Outlook inbox folder and it kept giving me the error you mention in your question.

My solution: only drag and drop about 100-150 emails at the same time.

That worked for me, please let me know if this works for you too so we can finally answer this question. The error Outlook gives is very weird and puts you on the wrong track.