Error 1603: "The update installer has encountered an internal error" and/or "Unable to Apply Patch" when installing a QuickBooks update

The following error occurs when installing a QuickBooks product update:

Error 1603: "The update installer has encountered an internal error" and/or  "Unable to Apply Patch"

This error can be caused by a damaged Microsoft Windows Installer file or a damaged QuickBooks  installation.

Click the appropriate link for your situation:

• QuickBooks was installed from a CD
• QuickBooks was installed from an online download

QuickBooks was installed from a CD:

To resolve this issue, uninstall and reinstall Microsoft Windows Installer 3.1:

1. Click the Windows Start button and select Control  Panel.
2. Double-click Add or Remove Programs.
3. Locate Windows Installer  3.1.
4. If Windows Installer 3.1 is in the list of programs, select it, click the Remove  button, and follow the onscreen steps to remove the program.
5. If the program isn't listed or if you uninstalled it in step 4, install the program from the QuickBooks CD:
   1. Insert your QuickBooks CD in the CD drive.
   2. Right-click the Start button and choose  Explore.
   3. Browse to D:\Qbooks. update error, . If necessary, change D: to the drive letter for your CD drive.
   4. Double-click the Windows Installer setup file:
      • QuickBooks 2007 and later: windowsinstaller-kb893803-x86.exe
      • QuickBooks 2006 and earlier: instmsiw.exe
   5. Follow the onscreen steps to complete the installation.
      • If Windows Installer 3.1 installs successfully, try installing the QuickBooks product  update again.
      • If Windows Installer 3.1 doesn't install successfully, download and install it from  Microsoft article 893803: Windows Installer 3.1. update error, . Note that this is a Microsoft product and Intuit can't provide support for third-party products.

If you continue to receive the error, reinstall QuickBooks to a new folder, and then update QuickBooks to install the product update.

If the above steps do not resolve the error, download the Microsoft Windows Installer CleanUp Utility from the Microsoft Support site, and  then reinstall QuickBooks. update error, . Please note that this is a Microsoft product and Intuit cannot provide support for third-party  products.

If this solution does not resolve the issue, you can read discussions and post messages and questions relating to your issue on the Intuit QuickBooks Community site for free or you can contact a technical support agent for additional guidance. update error, . Fees may apply.

QuickBooks was installed from an online download:

To resolve this issue, uninstall and reinstall Microsoft Windows Installer 3.1:

1. Click the Start button and select Control  Panel.
2. Double-click Add or Remove Programs.
3. Locate Windows Installer 3.1.
4. If Windows Installer 3.1 is in the list of programs, select it, click the Remove  button, and follow the onscreen steps to remove the program.
5. If the program isn't listed or if you uninstalled it in step 4, install the program from the downloaded QuickBooks installation file:
   1. Click the Start button and choose Run.
   2. In the Open field, enter %temp% and click OK.
   3. Double-click the folder for your version of QuickBooks (Pro, SimpleStart, Premier, Enterprise).
   4. Double-click Qbooks
   5. Double-click the Windows Installer setup file:
      • QuickBooks 2007 and later: windowsinstaller-kb893803-x86.exe
      • QuickBooks 2006 and earlier: instmsiw.exe
   6. Follow the onscreen steps to complete the installation.
      • If Windows Installer 3.1 installs successfully, try installing the QuickBooks product  update again.
      • If Windows Installer 3.1 doesn't install successfully, download and install it from  Microsoft article 893803: Windows Installer 3.1. update error, . Note that this is a Microsoft product and Intuit can't provide support for third-party products.

If you continue to receive the error, reinstall QuickBooks to a new folder, and then update QuickBooks to install  the product update.

If above steps do not resolve the error, download the Microsoft Windows Installer CleanUp Utility from the Microsoft Support site, and  then reinstall QuickBooks. update error, . Note that this is a Microsoft product and Intuit cannot provide support for third-party  products.

If this solution does not resolve the issue, you can read discussions and post messages and questions relating to your issue on the Intuit QuickBooks Community site for free or you can contact a technical support agent for additional guidance. update error, . Fees may apply.