I am back researching this same issue for a client. The file size is as if all the records still exists. The file has had all the records "disappear" multiple times. My client has Inventory advisor. Does yours? Also found a Sage City article that had a similar issue and suspicion was caused by AR Period End processing. I just ran a AR period end along with the rest of the modules checking the file after each.
I have restored the file from a copy in the past, I have manually reinitialized and imported in the past. Many of the Vendor Alias' that are created by the use of a primary vendor are missing from my client's files. I believe we had cleared out the file previously. I recreated what should be all of those records by importing from the IM_ItemVendor table and all of those 35K records are now missing.
This issue existed in 2019 and 2021 for my client. The article I found from January of last year was 2016 (maybe your client).
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Larry Bradford
Accounting Technology LLC Consultant and Owner
Accounting Technology, LLC
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