It seems Dropbox links are now being used for spam purposes. A couple of days ago, I was wondering why Google Apps’ Gmail keeps on rejecting every message I send with a Dropbox link. So I tried to shorten it with is.gd and my message went through. However, today I got the following message while trying to shorten another Dropbox link:
Sorry, the URL you entered may be linked to spamming and is listed either in the SURBL or URIBL lists. To prevent the possibility of using this site to facilitate spam, it has not been added to our database.
Please bear in mind that use of this service for spam purposes is prohibited (see terms and conditions) and any such URLs will be disabled, and misuse reported to the relevant authorities. I wonder if other Dropbox users are experiencing related issues.