How to enter a non-standard capital loss

[findingmyway]

Hello, 

I have an interest-generating investment for which I held "junior notes" that was held in a small LLC.  Interest and principal payments stopped several years ago but they continued to try and collect on bad debt.  Unfortunately, that wasn't possible and they wound down the company this year leaving me with a capital loss on the remaining principal. They provided documentation of the wind-down along with my capital loss statement but not in a traditional tax form, like a 1099.  I'm trying to figure out how to account for this capital loss in TurboTax. Currently, I have it entered in the investment sales section listing it as a statement provided by my brokerage that was not reported to the IRS.  This approach will require me to mail paper forms to IRS, which is fine. I just want to make sure it is the best way to capture this. All previous reporting of principal and interest was provide via 1099-INT.  

[ThomasM125]

You are correct to report this as a sale of investment, using the sale amount as $0 and the cost basis as your unrecovered investment amount.