hexadecimal value 0x00 is an invalid character, web site crashed when upgraded to .NET 3.5

Problem

When we upgraded to Microsotf .NET Framework 3.5, some web sites crashed. Here are error messages.

     Description: An error occurred during the parsing of a resource required to service this request.   
    Please review the following specific parse error details and modify your source file appropriately.
    

Parser Error Message: '.', hexadecimal value 0x00, is an invalid character. Line 2, position 1.

Source Error:

Line 1: <?xml version="1.0" encoding="utf-8"?>
Line 2: <xs:schema id="DataSetAdmin"
Line 3: <xs:annotation>
Line 4: <xs:appinfo source="urn:schemas-microsoft-com:xml-msdatasource">

Version Information: Microsoft .NET Framework Version:2.0.50727.1433; ASP.NET Version:2.0.50727.1433

Solution

Remove encoding attribute from your xml document.

From
<?xml version="1.0" encoding="utf-8"?>
To
<?xml version="1.0"?>

Navigator

Other Knowledgebase Articles

Basic SQL Hosting

# of Domains: 4
# of SQL Server Databases: 4
Disk Space: 50GB
Bandwidth: Unmetered
SQL Server 2016
Monthly: $4.99
More Information About Basic Shared SQL Server Hosting Plan

Express Hyper-V Hosting

Dedicated Memory:2GB
Disk Space: 120GB
Bandwidth: Unmetered
Windows 2016/2012: Free
Monthly: $11.99
More Information About Express Windows Hyper-V Server

Dedicated SQL Server

CPU: Quad-Core X3440 CPU
RAM: 16GB RAM
Disk: 2x120GB SSD + 300GB SATA
RAID: RAID 1
Bandwidth: Unmetered
Windows 2016/2012: Free
Monthly: $79.00
More Information About Dedicated SQL Server with SSD
Managed Kubernetes Hosting | Windows VPS Hosting | SQL Server Hosting | ASP.NET Hosting | DNN Hosting | Windows Hyper-V Hosting