How to Fix a Unity Build Hanging or Getting Stuck

A Unity build hanging is a stuck step. The log points at it. Here is how to fix it.

How to fix it

1. Check the editor log

The editor log shows the build's progress. The last step logged before the hang tells you where it is stuck — compressing a specific asset, importing, or an external tool. Start from what the log shows.

2. Identify a problem asset or process

A single corrupt or huge asset can hang compression or import. An external process (the IL2CPP or platform toolchain) can stall. Identify and fix or exclude the asset, or restart the stuck process.

3. Ensure enough resources

Builds need memory and disk space. A build that hangs (or swaps endlessly) may be out of memory or disk. Free resources, close other applications, and ensure enough disk for the build's temporary and output files.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Unity error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.