The Splwow64.exe process is used to translate the driver model of a 64-bit operating system and a 32-bit program. The Splwow64.exe process stays in the memory for additional time to increase system performance after a print job is finished. Therefore, the Splwow64.exe process does not end as expected when a print job is finished.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
After you apply this hotfix, the hotfix sets the default time-out value for the Splwow64.exe process to remain in memory to two minutes. Therefore, the Splwow64.exe process shuts down two minutes after the last print job is finished.
Prerequisites
To apply this hotfix, you must be running Windows 7 Service Pack 1 (SP1) or Windows Server 2008 R2 SP1.
For more information about how to obtain a Windows 7 or Windows Server 2008 R2 service pack, click the following article number to view the article in the Microsoft Knowledge Base: 976932 Information about Service Pack 1 for Windows 7 and for Windows Server 2008 R2
The hotfix is located at https://support.microsoft.com/en-us/kb/2815716, click on the blue Hotfix Download Available button and follow the steps from there.