This file has been reported to be part of a spyware/malware/trojan. It is likely that the problem you are experiencing is linked directly to the spyware/malware/trojan rather than an actual missing DLL-file and the recommended course of action is to first locate/remove the Malware. We do not recommend downloading this file.
DLL-Files.com Support says:
This is a possible manual solution for you 'handyman-fixers' out there:
WARNING: Do this at your own risk. manually changing the registry could cause system critical errors if done incorrectly, the instructions below are not guaranteed to work on your particular system setup.
Udconn.dll is part of a UDConn Dialer.
1. In windows XP/2K run regedit and search from the root for udconn.
2. Delete the key found in HKEY_CLASSES_ROOT\CLSID\ and find next entry. (Note ! Delete the whole key, named {number}, in the left windowpane)
3. Delete the 2 keys found in HKEY_CLASSES_ROOT\Interface\ (Note! As above) and keep searching.
4. Delete the key found in HKEY_CLASSES_ROOT\TypeLib\. Keep searching. (Note! You probably found the searchword in a subkey called 1.0, delete the parentkey named {number} above it)
5. Delete the keys HKEY_CLASSES_ROOT\UDConn.UDConnect and HKEY_CLASSES_ROOT\UDConn.UDConnect.1 and keep searching.
5. Delete the key in HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{xxxxxxx}
6. Most importantly, delete the key "komo-molair-htm" in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
7. Also delete HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\komo-molair-htm
Your computer should now be free of the UDConn dialler.