Error message: "Attempted to read or write protected memory."

 
ERROR MESSAGE
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

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.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

DESCRIPTION 

This error is not directly related to Telerik controls but occurs when trying to drop a Telerik control from the VS toolbox onto the designer workspace and then the file is checked out using SourceGear or SourceSafe.

Telerik was first contacted with this problem during VS2005's beta stage but the exception is related to machines with any VS2005 installation which works in conjunction with either SourceSafe or SourceGear Vault. Our research shows that it is caused by an AccessViolationException thrown by VS.NET. Such exceptions occur when a .NET program uses P/Invoke to call native methods (COM objects or DLL-exported methods). No Telerik control does that. 

So far we have found the following reasons for the exception:

• configuration/installation problems of the framework, VS.NET and/or SourceSafe/SourceGear (usually the SourceSafe/SourceGear installation is corrupted). Restarting of VS, IIS or the machine does not help;
• running 32-bit code which tries to call 64-bit one and vice versa (this appears on 64bit machines, i.e. 64-bit CPU, Windows or .NET 2.0 version).

SOLUTIONS
This error message is still being investigated and other solutions may exist. In case you are able to fix the problem in some other way than the described below, please let us know, so that we can update the article.

1. Try creating a new project - you should be able to use the Telerik controls in that project.
2. If you are still using the beta version of VS2005, update to the latest official version and try again.
3. A webserver with multiple worker processes may cause this inconsistency. The problem should disappear once the number of worker processes is set to 1.
4. Ensure that the VS.NET addin works in SourceSafe/SourceGear works. You can do that by checking files in and out of your repository (try checking out a page before dropping a control and see if it works). Try uninstalling all copies of VSS that you may have on your machine and install the latest version only.
5. If you use the 64bit version of .Net2, then review this Microsoft support article on switching from .NET1.x 32bit to .NET2 64bit: http://support.microsoft.com/default.aspx?scid=kb;en-us;894435, more importantly the ASP.NET 2.0, 32-bit version section and setting the 64bit Web Service to Prohibited.
6. Simply copy and paste the controls' DLLs and XML files into the bin directory.
7. If none of the above works, you may consider reinstalling the machine.

This problem cannot be observed with RadControls for ASP.NET AJAX