An oversize mail folder - Inbox or other - will cause an irrecoverable choke.
Temporary circumvention, with NS closed:
Either rename the Inbox to something else ( InboxZ ), and do NOT try to Open it when you bring up NS.
Or, preferably, move Inbox completely out of the NS file structure.
NS will create a new mail folder for any basic one that is missing.
Unfortunately, none of the text editors that are available for Windows (WordPad included) can handle oversized files. Do a search for [ "file split utility" } and take your pick.
Dave/Amrad's procedure is correct. But realize that the splitting program doesn't split on 'an email boundary'. One must do recursive split-and-edits (WordPad is fine for 'smaller' files) to get the resulting Inbox-1, Inbox-2 ... Inbox-N files to contain whole emails. Once the smaller mail folders will Open, then the contents can be reorganized in some logical way, such as by year, by sender, etc.
Oh, and remember to Compact the mail folders periodically. (This could
be the basic cause of this present problem.)
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