TL;DR - I had to create a new Windows user profile. It was a nightmare to get everything set up again but Revit is back.
I had my Revit 2026 experience something like this. I got the same or very similar error dialogs. I was still using 2024, but it only happened in 2026. I tried removing add-ins, updated my graphics card driver, and verified that the latest version of Revit 2026 was installed (it was, and had been for the last 3-5 months). I reached out to Autodesk and created a ticket, and they responded with a list of troubleshooting tips, some of which I'd already tried, some I hadn't, and one of which I couldn't because the crashing error:
►https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Revit-journal-reco...
►https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Revit-crashing-cli...
Kindly try below in sequence -
►Apply update Revit 2026.4
https://up1.autodesk.com/prd/2026/RVT/8B8F57BC-1883-3B67-957B-D23EF083B0F2//Revit_2026_4_0.exe
Further, clean temporary files, restart the machine and check, https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/How-to-delete-temp...
►Disable add-ins and check, disabling manually or uninstalling them completely is preferred -
https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/How-to-Disable-Add...
Step 2 - If no addins installed or uninstalling addins still create issues, kindly reset Revit to default as per article - https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/How-to-reset-Revit...
► Kindly log in via a new Windows user, open the software and check.
https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/How-to-create-a-ne...
Logging in with a different Windows user account was the only thing that worked, which confirmed that the issue was related to my Windows user profile. Our IT team created a new Windows account for me, and I had to recreate all my settings for every program. I basically spent a full day just doing that and am not done yet. But at least Revit works now. I didn't try a full uninstall/reinstall of Revit 2026, meaning not just uninstalling the program, but manually scrubbing all folders related to it. It's possible that could've done it, but unconfirmed. I believe other users have tried this to no avail. IT said that it's also possible a full uninstall of all Autodesk products could have solved it, but we didn't try that. It may be worth it if you have a lot of custom settings in your email, PDF reader, browser, etc. as I do. Had that worked, I would have only needed to update settings in a few products, instead of Windows and every program I use. Hope this helps anyone else experiencing this issue.