Hi Heather Serwa,
>> I can drag and drop files on one site, but not the other
Do you mean you cannot drag and drop a file from a Sharepoint site to email as an attachment?
Does this issue can be reprofuced on other users' Outlook?
Is there any error message when the issue occurs?
Then here we mainly focus on general questions about Outlook client. For concerns about permissions on SharePoint site, it is also encouraged to post a new thread to the SharePoint forum:
https://social.technet.microsoft.com/Forums/office/en-US/home?category=sharepoint
The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.
Best reagrds,
Yuki Sun
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