A customer and my dad keep getting the same error when view a specific product on our website. My dad is using firefox 3.5.6 as well as myself, but he gets the error and I do not.
http://www.medsupplier.com/Products/Brewer-Basic-Manual-Examination-Table__0985-4000.aspx <SPAN style="FONT-SIZE: 24pt; FONT-FAMILY: 'Times New Roman','serif'">Server Error in '/' Application.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p><SPAN style="FONT-SIZE: 24pt; FONT-FAMILY: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'">
<HR style="COLOR: silver" align=center width="100%" noShade SIZE=1>
<SPAN style="FONT-SIZE: 18pt; FONT-FAMILY: 'Times New Roman','serif'">Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.<SPAN style="FONT-SIZE: 18pt; FONT-FAMILY: 'Times New Roman','serif'"> <o:p></o:p><SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Arial','sans-serif'">Descript<b>ion: </B><SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Arial','sans-serif'">An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about
the error and where it originated in the code.
Exception Details: System.Web.HttpException: Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.
Source Error: <o:p></o:p>
[table class=MsoNormalTable style="BACKGROUND: #ffffcc; WIDTH: 100%; mso-cellspacing: 1.5pt; mso-yfti-tbllook: 1184; mso-padding-alt: 0in 0in 0in 0in" cellPadding=0 width="100%" border=0]
[tr style="mso-yfti-irow: 0; mso-yfti-firstrow: yes; mso-yfti-lastrow: yes"][td style="BORDER-RIGHT: #f0f0f0; PADDING-RIGHT: 0.75pt; BORDER-TOP: #f0f0f0; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; BORDER-LEFT: #f0f0f0; PADDING-TOP: 0.75pt; BORDER-BOTTOM: #f0f0f0; BACKGROUND-COLOR: transparent"][color=#000000><SPAN]The source code that generated this unhandled exception can only be shown when compiled in debug mode. To enable this, please follow one of the below steps, then request the URL:
1. Add a "Debug=true" directive at the top of the file that generated the error. Example:
<%@ Page Language="C#" Debug="true" %>
or:
2) Add the following section to the configuration file of your application:
<configuration>
<system.web>
<compilation debug="true"/>
</system.web>
</configuration>
Note that this second technique will cause all files within a given application to be compiled in debug mode. The first technique will cause only that particular file to be compiled in debug mode.
Important: Running applications in debug mode does incur a memory/performance overhead. You should make sure that an application has debugging disabled before deploying into production scenario.<SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'"> <o:p></o:p>[/color]
[/td][/tr][/table]<SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Arial','sans-serif'">
Stack Trace: <o:p></o:p>
[table class=MsoNormalTable style="BACKGROUND: #ffffcc; WIDTH: 100%; mso-cellspacing: 1.5pt; mso-yfti-tbllook: 1184; mso-padding-alt: 0in 0in 0in 0in" cellPadding=0 width="100%" border=0]
[tr style="mso-yfti-irow: 0; mso-yfti-firstrow: yes; mso-yfti-lastrow: yes"][td style="BORDER-RIGHT: #f0f0f0; PADDING-RIGHT: 0.75pt; BORDER-TOP: #f0f0f0; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; BORDER-LEFT: #f0f0f0; PADDING-TOP: 0.75pt; BORDER-BOTTOM: #f0f0f0; BACKGROUND-COLOR: transparent"]<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'"><o:p>[color=#000000> </FONT></o:p>
[HttpException (0x80004005): Unable to validate data.]<o:p></o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'"><o:p>[color=#000000> </o:p>
[ViewStateException: Invalid viewstate. <o:p></o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'"><o:p>[color=#000000> </o:p>
<FONT color=#000000>[HttpException (0x80004005): Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.]<o:p></o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
<SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: 'Courier New'">[color=#000000> ]</o:p>[/color]
[/td][/tr][/table]<SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'"><o:p> </o:p>
<SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'">
<HR style="COLOR: silver" align=center width="100%" noShade SIZE=1>
<SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Arial','sans-serif'">Version Information:<SPAN style="FONT-SIZE: 12pt; FONT-FAMILY: 'Arial','sans-serif'"> Microsoft .NET Framework Version:2.0.50727.1433; ASP.NET Version:2.0.50727.1433<o:p></o:p>