Spectrus: How to clear previous annotation suggestions

Description
Spectrus modules maintain a history of text used in annotation dialogs (for LC/MS, NMR, UV/IR, etc.). There is no in‑application option to clear this list. The history is stored in the Windows registry under technique‑specific keys and can be reset by deleting those keys.

Solution

1. Close all ACD/Labs applications.
2. Open the Registry Editor (regedit).
3. Navigate to the relevant keys for the data type you want to reset:
   • LC/MS:
     HKEY_CURRENT_USER\Software\Advanced Chemistry Development (ACD)\Spectrus_2025\MASS\Annotation Dialog History
   • 1D NMR:
     HKEY_CURRENT_USER\Software\Advanced Chemistry Development (ACD)\Spectrus_2025\1D NMR\Annotation Dialog History
   • 2D NMR:
     HKEY_CURRENT_USER\Software\Advanced Chemistry Development (ACD)\Spectrus_2025\2D NMR\Annotation Dialog History
   • Curve:
     HKEY_CURRENT_USER\Software\Advanced Chemistry Development (ACD)\Spectrus_2025\CURVE\Annotation Dialog History
   • UV/IR:
     HKEY_CURRENT_USER\Software\Advanced Chemistry Development (ACD)\Spectrus_2025\UVIR\Annotation Dialog History
   • Chromatography:
     HKEY_CURRENT_USER\Software\Advanced Chemistry Development (ACD)\Spectrus_2025\CHROM\Annotation Dialog History
4. For each technique where you want to clear the history:
   • Right‑click Annotation Dialog History and choose Delete.
5. Close the Registry Editor.
6. Reopen Spectrus. The annotation dialogs will now have empty or default suggestion lists and will start building a new history.