Here's my final take on this: Secureline, in a nutshell, is not compatible with Office 365's OneDrive file system, at least in a Win7 environment. As I mentioned above, I can force it to save and retrieve files on occasion, but not through the OneDrive interface that MS puts forward everytime you go to save or recall. After a couple days' back and forth with Support -- during which they had me do all sorts of log-filing and other tasks, which ultimately screwed up my OS for a day (my fault; hit wrong button in trying to find a hidden folder needed for that task) -- Support informed me, flatly, that Secureline is NOT compatible with Office 365. And they directed me to an MS page of gibberish, just for good measure. (See copied email below.) So, there you go.
Secureline works well for me in general. It is not compatible with Office, and Avast clearly does not advertise this fact in its sales material. If you want to use a VPN on a regular basis, and don't want to have to deactivate it everytime you save or access a OneDrive file, it should work for you. If this bugs you, don't buy it. It's not clear to me whether this is a universal problem with other VPNs, but I would think that the MS people, given that they are catering to business users, would have worked that problem out to some degree.
Begin copied note from Support:
Hello,
Thank you for your information and opinion. We are sorry for your inconvenience but MS office 365 has some specific conditions as you ca see e.g. here:
http://technet.microsoft.com/en-us/library/dn509532.aspxand there can be many another that aren't described in this document. Anyway we don't declare avast VPN is compatible with Office 365. We will monitor the situation in our customer base. The case has been closed.
Best regards,
Avast Software s.r.o 2nd level support team