Question
Having transferred my Oblivion save file from the old computer to the new one, I don't remember all mods I had on the old computer (which I don't have access to anymore).
Apart from guessing, is there any other way of knowing which mods was used with the save file?
P.S. AFAIK, I didn't use Oblivion Mod Manager.
Answer
Yes! Wrye Bash has a savefile browser tab that will show you a save's "master list", which is the list of mod files (and their order) that the save file depends on for all its object IDs.
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