On a Premiere timeline containing AE comps dynamic linked into it, if you open AE and save the file with your cursor still on the comp in Premiere, it will often unlink the file and require you to manually unlink it. This usually happens every time you save the AE file.
On my setup, my AE and project files are hosted on an SMB share on the local network. As far as I know this network is stable and without problems, except for this one particular bug.
Steps to recreate:
1. Create Project
2. Make video clip and right-click -> Replace with AE composition OR
- Import AE composition into project panel directly
3. Make sure project is open in AE
4. Leave timeline cursor on AE dynamic linked comp
5. Alt-tab into AE, then make a change to project and save
6. Alt-tab back into Premiere, and the project will unlink and be marked as missing media
To remedy:
Right click -> Link media, and the correct AE project will automatically be highlighted, meaning Premiere definitely already knows where the asset is and that it exists.
Possible fixes for this bug:
1. Make it so Premiere double checks when a file disconnects. Just look one more time to see if the project is still there
2. Tell Premiere to chill and give it a second before insisting the project has vanished
Version 24.0.0 Build S8, but this problem has persisted for years across many versions
Windows 10, up to date
Threadripper 3990X
Radeon 6800XT (up to date drivers)
Let me know if I can provide any more info.