Installing P8 eForms patch produces the following error java.io.FileNotFoundException

Symptom

When installing an IBM FileNet P8 eForms patch the installation fails and the following is displayed in the eforms_install_log_4.0.2.P.txt installation log file:

Install, com.installshield.product.actions.
XmlTransformer, err, ProductException: (error code = 601; message="
err"; additional data = [ProductException: (error code = 601; message="
err"; additional data = [java.io.FileNotFoundException:
\\<servername>\<foldername>\FileNet\Config\AE\eforms-integration.xml (The
network path was not found.)])])
STACK_TRACE: 13
ProductException: (error code = 601; message="err"; additional data =
[ProductException: (error code = 601; message="err"; additional data =
[java.io.FileNotFoundException:
\\<servername>\<foldername>\FileNet\Config\AE\eforms-integration.xml (The
network path was not found.)])])
at com.installshield.product.actions.XmlTransformer.productException
(Unknown Source)
at com.installshield.product.actions.XmlTransformer.install(Unknown
Source)
at com.installshield.product.service.product.
PureJavaProductServiceImpl.installProductAction(Unknown Source)
at com.installshield.product.service.product.
PureJavaProductServiceImpl$InstallProduct.
getResultForAppendProductAction(Unknown Source)
at com.installshield.product.service.product.InstallableObjectVisitor.
replaceComponent(Unknown Source)
at com.installshield.product.service.product.InstallableObjectVisitor.
visitInstallableComponents(Unknown Source)
at com.installshield.product.service.product.InstallableObjectVisitor.
visitProductBeans(Unknown Source)
at com.installshield.product.service.product.
PureJavaProductServiceImpl$InstallProduct.install(Unknown Source)
at com.installshield.product.service.product.
PureJavaProductServiceImpl$Installer.execute(Unknown Source)
at com.installshield.wizard.service.AsynchronousOperation.run(Unknown
Source)
at java.lang.Thread.run(Thread.java:801)

Install, com.filenet.installers.Action.
InstallSummaryLog, dbg, Errors occurred during the installation.
<ul><li>An error occurred and product update failed. Look at the log
file c:\FileNet\AE\eforms_install_log_4.0.2.P.txt for details.</ul>