I've solved this problem.

I had to add the following to my web.config

<httpHandlers>            <!-- Intersoft Control Resources-->            <add path="ISRes.axd" verb="GET" type="ISNet.WebUI.WebResourceHandler, ISNet.WebUI, Version=3.0.5000.1, Culture=neutral, PublicKeyToken=b1f2a8511635667a" validate="true"/>
        </httpHandlers>

So my final result in the web.config looks like this (to deploy too IIS 7)

<system.web>
        <customErrors defaultRedirect="/Errors/Oops.aspx" mode="On">
        </customErrors>
        <compilation debug="true" strict="false" explicit="true" targetFramework="4.0">
            <assemblies>
                <add assembly="System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
                <add assembly="System.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A"/>
            </assemblies>
        </compilation>
        <authorization>
            <deny users="?" />
        </authorization>
        <authentication mode="Forms">
            <forms loginUrl="~/Login" timeout="2880" name=".ASPXAUTH" protection="All"/>
        </authentication>
        <membership>
            <providers>
                <clear/>
                <add name="AspNetSqlMembershipProvider" type="System.Web.Security.SqlMembershipProvider" connectionStringName="ApplicationServices" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="/"/>
            </providers>
        </membership>
        <profile>
            <providers>
                <clear/>
                <add name="AspNetSqlProfileProvider" type="System.Web.Profile.SqlProfileProvider" connectionStringName="ApplicationServices" applicationName="/"/>
            </providers>
        </profile>
        <roleManager enabled="false">
            <providers>
                <clear/>
                <add name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider" connectionStringName="ApplicationServices" applicationName="/"/>
                <add name="AspNetWindowsTokenRoleProvider" type="System.Web.Security.WindowsTokenRoleProvider" applicationName="/"/>
            </providers>
        </roleManager>
        <pages controlRenderingCompatibilityVersion="3.5" clientIDMode="AutoID"/>
        <httpHandlers>
            <!-- Intersoft Control Resources-->
            <add path="ISRes.axd" verb="GET" type="ISNet.WebUI.WebResourceHandler, ISNet.WebUI, Version=3.0.5000.1, Culture=neutral, PublicKeyToken=b1f2a8511635667a" validate="true"/>
        </httpHandlers>
        
    </system.web>
    <system.webServer>
        <modules/>
        <validation validateIntegratedModeConfiguration="false"/>
        <handlers>
            <add name="ISRes.axd_GET" path="ISRes.axd" verb="GET" type="ISNet.WebUI.WebResourceHandler, ISNet.WebUI, Version=3.0.5000.1, Culture=neutral, PublicKeyToken=b1f2a8511635667a" preCondition="integratedMode"/>
        </handlers>
    </system.webServer>

Glad to hear the good news.

Should you need further assistance or run into any problems regarding our controls, feel free to post it into our community. We would be happy to assist you again.