I’ve noticed the problem before, but it was never annoying/frequent enough - usually just a restart made it go away. But now, I don’t think I am able to get into this project at all. Nothing is turning up in the default logs.
I still get the spinning icon so it looks like its its trying to load. Also the project is around 37 MB - I think its fully downloaded but there is something holding the process up.
TLDR: I had to delete the "designer" launcher entry from designer launcher, then re-add it manually to resolve the issue. I suspected my issue was due to importing launcher config from a different computer but could not reproduce the error thereafter.
TLDR Update: Seems my issue is related to ESET firewall settings, in a manner I don't quite understand. Will report back once I figure it out, but with firewall paused the problem goes away.
I came across this issue today.
Attempts to load a designer session resulted in a perpetual "loading" screen.
On the few instances designer actually loaded (I walked away for who knows how long) it was missing all Perspective configuration (its a Perspective based project).
Here are my observations, actions and results.
I restarted the computer (several tries) with no change in results.
Checked my internet connection, seems fine.
I then attempted to rename the "%USERHOME%.ignition\cache" as suggested by @nminchin but was blocked as the folder was in-use.
Using the File Locksmith (Windows PowerToy) I was able to see the file was in use by a java.exe process and a bunch of chromium.exe processes (even though I had already closed all Ignition apps).
I ended the java.exe task, which also eliminated all the chromium.exe tasks.
I tried launching a designer session again with the same results as before.
I then successfully renamed the "%USERHOME%.ignition\cache" folder after manually ending the jave.exe task.
Subsequent attempts to open designer initially seemed successful, an illusion of activity due to repopulating the cache but designer did not load in a timely manner.
The only contributing factor for the issue I can identify was that I recently switched computers and used the designer-launcher export/import features to bring over old configuration.
I then deleted the imported "designer" launcher entry in designer launcher and created it again from scratch.
After that the designer session loaded quite fast and showed Perspective configuration.
Figuring I hadn't wasted quite enough of my time, I reimported the launcher config that I suspected was the root of the cause to reproduce the issue, but could not reproduce the issue thereafter.
Update: After computer restart the issue came back and I narrowed it down to my ESET firewall (corporately controlled), I had paused that firewall during earlier testing for unrelated reasons and it appears that was the difference, not anything else. As it did not manifest as a complete block (I was prompted to enter credentials and pick a project) a firewall issue was not top of mind.
It is now September 15, 2025. The previous methods have all failed. However, you can adjust the memory size in the project under designerlauncher.exe. There is no need to clear the cache. Originally, my memory size was 1024m. After adjusting it to 4096m, it can run smoothly.