Reasons I Migrated From DNN Software to WordPress?

I was a DNN Software (formerly DotNetNuke) fan from past 15 years. When I created my personal Website in 2005, I used DNN Software. We could host multiple Websites on a single DNN instance was a really great idea. For hosting multiple Websites, I created domain alias which resulted in cheap hosting for couple of […]


Recommended Droplet Size For Hosting Multiple Websites

Recently I migrated my 4 Websites from shared hosting to Digital Ocean droplet. From past couple of months, I have been running 4 WordPress Websites (individual instances) and 1 .Net Core 3.0 instance along with email service on this droplet and it is working out fine. Website Usage Here is a list of need for […]


.Net 3.5 System.Web.UI.DataVisualization namespace does not exists

I was trying to compile an inherited VB .Net code that uses .Net 3.5 framework. When I compiled, it gave the following error The type or namespace name ‘DataVisualization’ does not exist in the namespace ‘System.Web.UI’ (are you missing an assembly reference?) Whatever answers I tried to find online could not give me details for […]


Webmin Postfix: How to solve “Host or domain name not found”

Error Host or domain name not found. Name service error for name=”XYZ” type=AAAA: Host not found Host or domain name not found. Name service error for name=”XYZ” type=A: Host not found Here XYZ is the host name of the droplet and NOT the domain name. For example if my server’s Fully Qualified Domain Name (FQDN) […]


Webmin Let’s Encrypt: XYZ is not a valid e-mail address

Error acme.messages.Error: urn:ietf:params:acme:error:invalidEmail :: The provided email for a registration was invalid :: Error creating new account :: “XYZ” is not a valid e-mail address Root Cause In my case, I created Virtual Server without the email feature enabled. Hence when Webmin tried to generate Let’s Encrypt SSL Certificate, it used the default email address. […]


Weird errors for VB .Net classes defined in App_Code folder

Recently I was making a .Net 3.5 webforms application compile on my computer. The application was written in VB .Net. There were couple of classes which were causing weird issues. Visual Studio compiler generated “variable not declared”, “Exception not declared”, “End Sub does not have matching sub”, “line continuation character does not work in VB […]


Webmin Let’s Encrypt Throws “Failed to Establish a New Connection”

Error requests.exceptions.ConnectionError: HTTPSConnectionPool(host=’acme-v02.api.letsencrypt.org’, port=443): Max retries exceeded with url: /directory (Caused by NewConnectionError(‘<urllib3.connection.VerifiedHTTPSConnection object at 0x7f94951b7860>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution’,)) Root Cause When Webmin tries to send request to Let’s Encrypt, Let’s Encrypt is trying to get the response from the Website index page. If Let’s […]



How to run a single instance of WinForm application?

Following tutorial provides an example to run a single instance of WinForms application using Mutex. There are multiple ways to achieve the same result but this is kind of neat solution in my opinion. Add following SingleInstance class in your project. Here is how to use it in Program.cs > Main function

.Net

Fixed – WordPress User Role dropdown is blank

Issue When I try to add a new user in WordPress under Admin > Users > Add New User, it shows blank dropdown. Root Cause I manually tried to change the WordPress prefix after WordPress blog was created. I made change only within wp-config.php and renamed tables but it required change in data as well. […]