I am getting error "An error was encountered while processing your request.

1. This error can be safely disregarded

2015-04-30 08:31:35,648 [ajp-/0.0.0.0:8009-1] ERROR com.appiancorp.process.runtime.activities.QueryRdbmsActivity - Unable to convert to expected Date/Time Java types
java.lang.NullPointerException

This message, which is a false positive, is logged when using the Query RDBMS activity to retrieve date/time columns, if the column contains null's that error is displayed in the application server log but it has no impact at all.

2. As the other users suggest the issue seems to be this expression assuming it's part of the problematic model

ERROR com.appiancorp.process.engine.ExpressionGroup - An error occurred while evaluating expression: =if(ength(pv!arrtxtBillToIDValues)>1,pv!arrtxtDescriptionVaues,pv!txtInsurerAddresName)

3. The fact that you're getting a generic browser pop-up instead of the Appian's pink error message indicates one of two things:

---> 3.1 The URL you're using to access Appian doesn't match conf.suite.SCHEME and conf.suite.SERVER_AND_PORT in custom.properties

----> 3.2 Or you are using IIS and haven't disabled the Custom Error Pages which prevents Appian from interpreting the HTTP error code correctly to display a more meaningful message (see forum.appian.com/.../e-120482)

To get a better error message:

1. Click on your IIS Site -> Error Pages -> Edit Feature Settings -> Select "Detailed Errors" only
2. Disable the custom error pages IIS Site -> .NET Error Pages -> Edit Feature Settings -> Off