Just to add to what **kluelos **was saying; under normal circumstances the downloads.xml (the file where BC saves its tasklist) is found in the Users%userprofile%\AppData\Local\VirtualStore\Program Files\BitComet or in your case in Users%userprofile%\AppData\Local\VirtualStore\Program Files (x86)\BitComet.
If you say that by reverting to v.1.15 you get back your tasklist it’s obvious that the downloads.xml doesn’t get overwritten in v.1.16 but instead the application reads it from another file (although it shouldn’t).
To be sure, you should make a backup copy of that file (in v.1.15) and store it somewhere else, as kluelos said (you can make sure that you’re looking at the right .xml file by opening it and looking inside; among all the gibberish you should see the names of your tasks).
Now, before trying to overwrite it as he instructed you, please add a task in the blank tasklist and exit BitComet. The new tasklist should be saved, now. Then restart BC to check if indeed it saved the tasklist. If it did then go and find that downloads.xml file (this could be a bit tricky, because it probably resides somewhere else than the original one from v.1.15 - check the real C:\Program Folder for it too). But even if it doesn’t save the tasklist and you get again a blank list when restarting BC you should, still, be able to find the file (it will have just a few xml tags but no record of any of your tasks).
I’m asking you to add a task to the list, just to make it easier to verify that you’re looking at the right file (and to check if the v.1.16 still can save its tasklist but does it in a different place or maybe it can’t do that at all).
Moreover you should make sure that User Account Control is not disabled during these operations and that you are not running BC with elevated privileges (i.e. started with Run as administrator command).
So, basically, we would want to know where do you find the downloads.xml for v.1.15 and the one for v.1.16, because they’re obviously different files in your case.
Why am I asking you to do all this?
Because lately we’ve been seeing tons of posts like yours, from people who in a way or another have lost their tasklist under Vista or Win 7. And no matter how hard I’ve tried I couldn’t manage to reproduce that behavior. None of us could, for that matter.
So, obviously, we’d like to understand what is different in your setup that is causing this kind of error.
I’ll give here a short clarification for all this folder madness, in Vista and Win 7. If you’re familiar with all that you can just ignore the following lines.
In Vista and Win 7, even when you log in with an administrator account you get assigned for current use a standard user access token (derived from the standard Limited User Account). That goes even for the instance of Explorer that you see on screen after Windows started. Whenever any application needs to perform any task requiring administrative rights it asks Windows for elevation and you get that annoying pop-up from UAC asking your permission. Once given permission Windows assigns the app the admin rights token. But under normal circumstances most of your applications will run under LUA access token. This has some consequences.
Starting with Vista, applications can no longer write into the system protected areas of file system and registry (among other things Program Files is one of them) unless they are running with elevated rights (under administrator token). This is part of the UAC (User Account Control) mechanism introduced with Vista and in order that the existent (non-Vista compatible) applications to cope with that another mechanism was introduced: data virtualization.
What data virtualization does, is intercept all the write and subsequent read operations to system protected areas (Program Files included) of the applications running under LUA access token and redirects them to a per user location located under the virtual store folder: Users%userprofile%\AppData\Local\VirtualStore\Program Files. It does that without the application’s assistance, so, the process is transparent for the application which believes that it did write or read from the real Program Files directory, in our case.
However, there are several cases when data virtualization gets disabled (when the application is run under admin token, when UAC is turned off, when the application has a embedded manifest requesting for elevation and is run under admin account etc.) which in turn will, sometimes, lead to problems much like yours.