Torrent Client Versions on PMSS

On most Pulsed Media seedboxes, the account chooses which release of rTorrent, qBittorrent, Deluge and Transmission it runs, from up to 25 builds, without a reinstall or a support ticket. Before each switch the panel backs up the rTorrent, ruTorrent, Deluge and qBittorrent configuration, and a new version that fails to start is replaced by the previous one automatically.

qBittorrent offers each of its versions linked against libtorrent 1.2 and against libtorrent 2.0. On a few servers fewer builds are installed. There a client's version section lists only the installed builds, which can be just the server's own build. Transmission has no server build, so where its builds are not installed it has no section. Where Configure shows no version section at all, the panel offers no version choice for that account. None of this depends on the plan or product, and no account setting changes it.

Where the version controls are

The controls sit on the ⚙ Configure tab, the last tab of the panel (see Apps Tab on PMSS). qBittorrent version, Deluge version, Transmission version and rTorrent version are sections of their own, in that order, right after the Apps section. The section list on the left links each of them, under Apps.

Each one shows the build that is running, a list of the builds on offer, an Account password field and a Switch version button, and after a switch the result of that switch. The list opens on the build currently selected and names qBittorrent builds by version and libtorrent generation, for example 5.2.4 (libtorrent 1.2).

The qBittorrent version section: the running build, the result of the last switch, the build list, the password field and the Switch version button.

The rTorrent version section, running the 0.16.25 build.

Builds on offer

As of October 2026, on a server with every build installed:

Client	Builds	Starts on
rTorrent	system; 0.9.8-r16 (jesec's rTorrent 0.9.8 fork); 0.9.8-stickz7.2 (the stickz community fork of rTorrent 0.9.8); 0.16.25 (upstream rTorrent)	0.16.25 for accounts that never switched (see below)
qBittorrent	system; 4.3.9, 4.4.5, 4.5.5, 4.6.7, 5.0.5, 5.1.4 and 5.2.4, each with libtorrent 1.2 and with libtorrent 2.0	system
Deluge	system; 2.0.5, 2.1.1, 2.2.0	system
Transmission	4.1.3, 4.0.5	off until a build is chosen

system is the build the server installs for every account. libtorrent is the library that does the BitTorrent work inside qBittorrent. The downgrade message names qBittorrent builds in short form, for example 5.2.4-lt2.0 for 5.2.4 (libtorrent 2.0).

rTorrent 0.16.25 becomes the build of an account that has never switched rTorrent, whose rTorrent custom settings are unedited and whose ruTorrent files are the ones the panel provides. It takes effect at that account's next rTorrent restart. Accounts that switched, or changed those files, keep what they run.

Which build to choose

Keep the build the account starts on unless there is a reason to change it.

rTorrent: 0.16.25 is the newest upstream release in the list. If the account's custom settings rely on commands 0.16 removed and should stay as they are, use one of the 0.9.8 builds.
qBittorrent: for large torrents or frequent rechecks, use a 5.x libtorrent 2.0 build (5.0.5, 5.1.4 or 5.2.4). PMSS runs those with qBittorrent's threaded read/write disk mode. The system build and the 4.x libtorrent 2.0 builds keep the older POSIX disk mode, which works on libtorrent's network thread and can freeze the web interface during a recheck.
Deluge and Transmission: keep Deluge on system unless a specific release is needed. Of the two Transmission builds, 4.1.3 is the newer.

Switching

Pick the build in the list.
Type the account password.
Press Switch version and confirm.

The panel then backs up the rTorrent, ruTorrent, Deluge and qBittorrent configuration and torrent session state (the same backup the Backup and restore section offers for download; media files are not part of it), stops the client, points the account at the chosen build and starts it. rTorrent and qBittorrent count as started only when the new build is still running a few seconds later. On success the section reads "Deluge selected: 2.2.0" (with the client and build switched to) and the page reloads.

The switch changes the program, not the data: downloaded files stay where they are.

A switch of qBittorrent or Deluge also turns that app on in Apps, so it shows as running there and is restarted if it stops.

After a switch: Deluge 2.2.0 running, and the result of the switch under it.

Three rules apply:

rTorrent must be running. If it was stopped with Stop in Apps, start it there first.
One switch per client at a time; a second request while one is running is turned away.
A move to a lower major release is refused, because older releases can corrupt the data a newer one wrote. In the current list this means qBittorrent 5.x back to 4.x. For a rollback that keeps the data, open a ticket.

When a switch or a build fails

If the new build does not start, the panel stops it, points the account back at the previous build and starts that one. The section then reads "switch failed; previous version restored." Nothing more needs doing. If the previous build cannot be started either, the section reads "switch failed; manual recovery is needed." and the client may be stopped: open a ticket.

rTorrent 0.16 and custom settings

rTorrent 0.16 renamed or removed some settings commands that 0.9.8 understood. PMSS starts 0.16 with its compatibility mode for the old names, which covers the panel's own settings and ruTorrent. A line in rTorrent custom settings that uses a command 0.16 removed outright still makes it quit at start.

When a selected rTorrent build quits within 20 seconds three times in a row, the account runs the system rTorrent instead, so torrents keep seeding. The selection itself is not changed, and the section says what happened:

rTorrent running the system build because the selected 0.16.25 build kept stopping right after start.

To return to the selected build, fix or remove the offending line in rTorrent custom settings, then switch rTorrent to a different build and back. Switching to the same build again does not clear the fallback; switching to another one does. The 0.9.8 builds (system, r16 and stickz7.2) accept the old commands unchanged.

Transmission

Transmission is off until a build is chosen. Choosing one starts it. The first time, its web interface can take a few minutes to answer.
Once a build is chosen, Transmission has a row in the Apps list with Open, Restart and Turn off while it runs. Turn off keeps it stopped until Turn on is pressed.
Switching Transmission versions while it is turned off is refused; turn it on first.
Its web interface is at /user-username/transmission/web/ on the panel address, behind the same login as the panel.
Its settings are not part of the configuration backup.

Transmission's own web interface, opened from the panel address, downloading the Debian netinst image in a test account.

Troubleshooting

The panel says	Meaning	What to do
Start rTorrent in Apps before switching versions.	rTorrent was stopped with Stop in Apps	Start it in Apps, then switch
Start Transmission in Apps before switching versions.	Transmission was turned off in Apps	Turn it on in Apps, then switch
A … switch is already running.	Another switch of that client has not finished	Wait for it, then try again
Downgrading … can corrupt existing data; switch refused — open a ticket for a data-preserving rollback.	The chosen build is a lower major release than the one that last ran	Choose a build of the same or a newer major release, or open a ticket
… switch failed; previous version restored.	The new build did not start; the previous one runs again	Nothing; the client is back as it was
… switch failed; manual recovery is needed.	Neither the new nor the previous build started	Open a ticket
Running: system, because … kept stopping right after start	The selected rTorrent build quit at start three times; the system build runs instead	Fix rTorrent custom settings, then switch to another build and back
Running: system; … starts at the next rTorrent restart	A build is selected, and rTorrent has not restarted since	Restart rTorrent in Apps, or leave it to start at the next restart
Running: not running	No process of that client is running	Use Start or Turn on in Apps

At Pulsed Media

Version choice is part of PMSS, the open-source platform Pulsed Media has developed in-house since 2010. The builds come from the PMSS client catalogue: each one is downloaded once per server, checked against a pinned checksum and shared by every account that selects it. See seedbox plans.