The aaclient.dll error code belongs to a program running from the Microsoft Windows Operating System.  In order to determine if this error relates to a virus, you have to establish the location that aaclient.dll is running from on your PC.

A manual search for this file will be next to impossible, as it will involve a complete search of your computer’s registry: this space on your computer is reserved for files (like Dynamic Link Library or DLL files and others) shared by multiple programs. Most users do not perform the recommended registry maintenance on their computers; therefore, a single machine may contain hundreds of registry errors.  The easiest way to handle this issue is to scan your computer.

Click below for a scan that will uncover all your registry errors.  Then select ZookaWare PC Cleaner as your registry restoring software.  It will fix your errors quickly, and then you can set the program for regular scans that will prevent this situation in the future.