We are working on a project shot on 4 5dMarkIVs.
During the editing process, some of the footage is showing as missing.
The footage is still on the drive but there is no re-link option anymore.
I'm in between a critical project and I've tried many options but no avail.
Those clips have black thumbnails, which can be different from missing. Select a black clip in the timeline, then do SHIFT+F to find the corresponding browser clip. When located in the browser, right-click and "Reveal in Finder". Is the clip there and will it play?
If so this could be a cache or render file problem. You can delete all render files by selecting the project icon in the browser, then Files>Delete Generated Project Files>Delete Render Files.
There is no built-in command to delete cache which is thumbnails and waveforms. To do that modify library properties to place cache in a separate folder. Select the library icon in the left sidebar, then in library inspector pick Storage Locations>Modify Settings, and pick a separate folder for cache. It will then ask "Do you want to move your render files?" You say "Don't include". This clears out the thumbnail and waveform files. In the future (if necessary) you can use Finder to delete the contents of the cache folder.
Do the above steps and report the results. For actual missing media, the clips are red and the procedure is below:
In the event browser, select one of the red "missing" clips. Then select Files>Relink Files. Give the location. You can point to the top-level of the drive - it will rapidly search the entire drive for the file.
If that works, select all the other red clips at once, then relink them. You can usually search for the term "Missing" to isolate these.
This is only for orig. media clips. If using proxies there is no relink option, the only reliable option is rebuild them.
Also please state where the media files and library are. Are they on a local drive, is that drive ExFAT or HFS, or are they on a NAS? Were they previously on a NAS then copied to a local drive? If a NAS is that using SMB or NFS?