[4.14.X Bug]: Print String Randomly Stops Working

Ever since the release of 4.14, PrintString has randomly stopped working for no apparent reason. It seems to happen after an hour or so of working in UE4 and I have not been able to find any reliable ways of reproducing it.

This bug happens in ALL of my projects, I have not had a single session since 4.14 where PrintString hasn’t stopped working.

The only way of fixing it that I have found thus far is to restart the entire editor. All of my projects are hooked up to source control*(Perforce)* so I’m not entirely sure if that might have something to do with it.

If this has already been reported I’d love to get the tracker ID if possible! PrintString is my main method of debugging, and it constantly breaking is so frustrating I’m considering downgrading back to 4.13…

Are the printStrings still being displayed in the Output Log?

I’ll take a look next time it happens and report back!

Sorry for the delay, I just checked and they do indeed show up in the Output Log - they only fail to show up in the PIE window.


I did some research and found that this has been reported a few times before, some people reported that it would work again once displaying the FPS in the PIE window.

This unfortunately made no difference for me.

Hi Dealman,

I believe this is caused be some debugging tools. They stop things from printing to the screen and there has been bugs in the past related to this.

In 4.14.3, you can reproduce this by setting something to print to screen > PIE > then press the ’ - apostrophe key to bring up the debugger > press again to remove the debugger. Now, nothing will print to screen.

This is fixed and working properly again in the 4.15 Preview 1. Could you try reproducing your exact issue there and see if it was also fixed?

I just had this happen again in 4.15.1 in a project I created barely an hour ago, an empty one.

All I’ve done is import a mesh and made a pawn BP with it. What’s even more peculiar is I can’t even open the debugger via the apostrophe key.

However, if I make a new level and play - I can print strings again. So this time around it’s definitely something to do with maps.

One possible cause may be that I moved the map to another folder and then used Fix Up Redirectors on the content(root) folder. Maybe this is what breaks it?

Sorry for the delay.

I was able to reproduce this in 4.15.1 using the ‘map moving’ step you mentioned. That seems to be the key.

However, I also tried to reproduce this in our latest internal build using the same steps and this bug doesn’t seem to be present there. So you should see this fixed in a future engine release.

Unfortunately I haven’t found a way to fix the issue once it happens; besides creating a new map like you mentioned. Maybe the best workaround in the meantime would be to avoid it altogether by not moving any .map files around. We always recommend to not move any files unless it’s absolutely necessary.

This still happens to me in an empty template when fiddling with a custom player controller and the debug camera(apostrophe key and then tab).

All these issues with Print String has resulted in me having to restart the editor every 5 minutes. Print String is my main source of debugging as it’s convenient, but this is making it utterly useless.

Really hoping this will be fixed in 4.16 because this bug has been around for far too long now.

Same issue as OP this happens in every single version it has never been fixed. Can we please please please have this bug fixed as I really really need the Print BP node to work.

Actually I think my problem is different as I can’t fix it by changing maps and also mine is with cooked builds and not in PIE runs.