ConColl is a debt management software that  simplify the process of collections and accounts receivable management. With features such as auto dialer, batch processing, client management  and many more.
ConColl is available in a free and paid version, free version is limited to 100 accounts and 1 user, download a copy  here . You can browse the user manual here. Give us a call if you need help with installation.
ConColl user interface is compatible windows XP, 7 and windows 10.

Features
Account management
Accounts import (CSV, XLS)
Document management (attach files and images to accounts)
Batch processing
Call log
Client management
Notes
Account level security
Dashboard (monitor collectors in real time)
Auto dialer
Search
Letter generation (using MicroSoft word document automation)
Reports
Performance management
PBX integration (Asterisk)