While utilizing NAV with NAVXtender to add documents. we had a group of users unable to add links in NAV. 

The exact error is "Failed to add Record Link. Unable to connect to the remote server". It still adds the file to the remote location, just doesn't add the "link" to it. Of the 8 users who all use the exact same configuration and have roughly the same permissions, only 3 cannot add a record link. It is extremely baffling. The 3 users can manually add the link without issue, so we know its not a user permission issue. 

Any ideas?