We built this legacy application back in 2007 and have a major upgrade in 2009 and has been running since then but then there is not much activity since 2014. Then reassure-ct again in late 2015.

Solutions

Couple findings

Error on the session

This is a bit shocking cause the .cs file is never being changed since 2009 !!!

Solution: Change the code accordingly to handle the missing handling of Session.

Find another one that is related to Debug mode. Set: <compilation debug=”false”> in Web.Config. There is a possibility that there is a bug previously and didn’t set back into False.

http://blogs.msdn.com/b/prashant_upadhyay/archive/2011/07/15/pros-and-cons-of-using-debug-true-in-asp-net-applications-in-production-environment.aspx

Validation of ViewState MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validation key and validation algorithm. AutoGenerate cannot be used in a cluster.

Turn out that the database server is registered under web.config still using the new production server. Need to change to a new server.

The application message came up: “You have a duplicate in MostLeast Preferred section. The option only can be used once of those questions. Please re-select it again.” Check the answer in the application and no duplicate answer.

Turn out that the actual matrix answer records in the database table have a duplicate for that particular question. Looks like entering twice. Not sure causing this at this stage. However, removing the duplicated entries solves the problem.

Credits

Photo by Pixabay: https://www.pexels.com/photo/application-blur-business-code-270408/

[Notes: Pageviews – 1,175 – before migrated from the Dewalist Blog website on 09/08/2020]