Unable to cast object

I have a master page and a content page to that master.

When I try to work with them I get an inconsistent error of casting ability
and it happens irregularly, which means sometimes it can work and sometimes
not, without making any changes to the code.

Is this a bug concern? Or do you have any advice for this issue?

Here is the error message I get:

Server Error in '/LocalIms' Application.
------------------------------------------------------------ --------------------

Unable to cast object of type 'ASP.masterims_master' to type 'MasterIms'.

Description: 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.InvalidCastException: Unable to cast object of
type 'ASP.masterims_master' to type 'MasterIms'.

Source Error:

Line 22: protected void Page_Load(object sender, EventArgs e)

Line 23: {

Line 24: MasterIms master = (MasterIms)this.Master;

Line 25: master.LeftBarPlayerVisibility = false;

Line 26: master.LeftBarSearchVisibility = true;

Source File: c:\Documents and Settings\liors\Desktop\LocalIms\Sm.aspx.cs
Line: 24

Stack Trace:

[InvalidCastException: Unable to cast object of type 'ASP.masterims_master'
to type 'MasterIms'.]

Sm.Page_Load(Object sender, EventArgs e) in c:\Documents and
Settings\liors\Desktop\LocalIms\Sm.aspx.cs:24

System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o,
Object t, EventArgs e) +13

System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Obje ct sender,
EventArgs e) +45

System.Web.UI.Control.OnLoad(EventArgs e) +80

System.Web.UI.Control.LoadRecursive() +49

System.Web.UI.Page.ProcessRequestMain(Boolean
includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3745

------------------------------------------------------------ --------------------

Version Information: Microsoft .NET Framework Version:2.0.50727.42; ASP.NET
Version:2.0.50727.42

Re: Unable to cast object

Dave wrote:
> I have a master page and a content page to that master.
>
There was no way for you to know it (except maybe by browsing through some
of the previous questions in this newsgroup before posting yours - always a
recommended practice) , but this is a classic asp newsgroup. ASP.Net bears
very little resemblance to classic ASP so, while you may be lucky enough to
find a dotnet-knowledgeable person here who can answer your question, you
can eliminate the luck factor by posting your question to a group where
those dotnet-knowledgeable people hang out. I suggest
microsoft.public.dotnet.framework.aspnet.

I've not started using that technology yet so I cannot attempt an answer
here.

--
Microsoft MVP - ASP/ASP.NET
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don't check it very often. If you must reply off-line, then remove the
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