This error message should happen with ACT! by Sage 2007 (9.0).

Close ACT. Download and Save the attached file at the bottom of the page to your desktop or the desired folder.

Open Windows Explore and browse to C:\Program Files\ACT\Act for Windows and open the Plugins folder.

Delete these files:

4Advisor.dll
CS_orgxnet2006.dll

Open Windows Explore and browse to C:\Program Files\ACT\Act for Windows and open the Tools folder.

Delete these files:

A4ALayoutTab.dll
AdvisorPrefMailButton.dll

Go to your desktop and locate 4Advisors140.zip. Open and and locate 4Advisors.dll - copy to
C:\Program Files\ACT\Act for Windows\Plugins

Next, copy the files A4ALayoutTab.dll and AdvisorPrefMailButton.dll to the folder
C:\Program Files\ACT\Act for Windows\Tools

Act4Advisors
http://software4advisors.com 
Allied Financial Software, Inc.