I am working on a return in ProConnect and encountering a persistent $4 million Alternative Minimum Tax (AMT) liability that I cannot resolve. The taxpayer's regular taxable income is only $80,719, and there are no apparent entries or adjustments that explain this high AMT liability. Here’s what I’ve checked so far:

1. Form 6251 Input Screen:

   • I reviewed every line on the Form 6251 input screen, and all fields are empty. There are no manual entries contributing to the AMT calculation.

2. Stock Transactions (Schedule D):

   • The taxpayer participated in a Section 423(c) Employee Stock Purchase Plan (ESPP). However, I deleted all related stock sales from Schedule D, and the AMT liability still remains.

   • There were no incentive stock options (ISOs) involved, so AMT adjustments for ISOs should not apply.

3. Interest Income Screen:

   • The software directed me to the Interest screen, but there is no input for tax-exempt interest or private activity bonds that could explain the AMT adjustment.

4. Depreciation and Other Adjustments:

   • I checked the depreciation screens and found no differences between regular tax and AMT depreciation methods that could account for this liability.

   • Other miscellaneous income screens (e.g., carryovers, NOLs) also show no relevant entries.

5. Diagnostics and Hyperlinks:

   • I used ProConnect’s diagnostic tool and clicked through all blue-shaded hyperlinks on Form 6251 to trace back the source of the AMT calculation, but I haven’t been able to identify any data causing this issue.

Despite these checks, the $4 million AMT liability persists, and I cannot locate its source. Could this be a software glitch or an automatic adjustment that ProConnect is applying incorrectly?

Specific Questions:

1. I see on Form 6251 line 2g, there was a fictional $14,578,946 "Interest from specified private activity bonds exempt from the regular tax" showed up from nowhere.  I checked the interest income input screen but not able to see anything.  How do I remove this amount?  

Any guidance on how to resolve this issue would be greatly appreciated!