When something goes wrong

Read the status bar first

It reports what just happened in plain words. When something appears to do nothing, it has usually already told you why.

Greyed out buttons and menu items explain themselves when you hover them.

Reading an error

A failed job keeps its error on its row in the queue rather than showing a dialog that vanishes. Open Export → Show Job Queue and read it there.

Every editor also shows the command it was about to run, selectable so you can copy it. When an export produced something you did not expect, comparing the command against what you thought you asked for usually settles it in a few seconds.

The buttons are greyed out

Clip, Combine and Convert stay disabled until media is loaded. Most other disabled controls need something selected. Hover for the reason.

A file will not play in the preview

Its codec is one the preview engine cannot decode. The file still clips, converts and exports correctly. The media bin shows the codec.

If you need to see it while you work, convert it to H.264 first and edit the converted copy.

Next Frame and Previous Frame are disabled

The file's analysis has not finished. Wait a moment. Without it the program does not know the frame rate, and stepping by a guessed frame duration would put your cut in the wrong place.

My cut landed slightly off where I clicked

On audio, cuts snap to the nearest zero crossing so the edit does not click. It is deliberate and the difference is milliseconds.

Sound drifts away from picture in a combined file

The pieces had different frame rates. Joining 23.976 material with 30fps material produces exactly this, and it grows as the piece runs rather than staying constant.

Convert everything to one frame rate first, then combine.

A segment lost its sound

Either Keep Segment is cleared on that segment, or the segment is a freeze. A frozen frame is encoded with no audio whatever the keep setting says.

The export is much bigger or smaller than expected

Size is bitrate times duration. Check the CRF or bitrate in the properties panel, and check the output height. If you need a specific number, turn on Target file size.

The export failed

Common causes, in the order they happen: no write permission in the output folder, a source file that moved or was unplugged partway through, a disk that filled up, and a format combination that does not exist. The queue row names which.

The picture is squashed or has unexpected black bars

The Fit or fill setting against a source whose shape does not match the output. Fit keeps everything and adds bars. Fill fills the frame and crops the overhang.

The export looks washed out or crushed compared with the source

A levels mismatch, where black is being read as 16 instead of 0 or the reverse. It shows as a uniform lift or crush rather than a colour shift. See Why your export looks different from your edit.

Captions are cut off at the edge of the frame

Lines wrap at 42 characters, so a caption that still runs off is placed too close to the edge rather than too long. Increase Caption margin, or reduce Caption font size.

Settings and presets do not survive a restart

The program folder is somewhere Windows will not let it write, which is usually Program Files. Move the whole folder somewhere you own.

The window layout is a mess

View → Restore Default Layout. Reach for it early rather than trying to drag your way back.

Starting clean

Close the program, rename the data folder beside the executable to something else, and start it again. You get a fresh data folder with default settings, and your old presets are still in the renamed folder if you want anything back out of it.

Rename rather than delete. It costs nothing and it is reversible.

Windows blocked the program

It is not code signed. Choose More info, then Run anyway. To confirm the download first: certutil -hashfile AVPrep2-portable-0.1.0.zip SHA256, and compare against the download page.