Question

I’ve using vb.net 2003 and some of the times this error arises. Can anyone know on how this error arises and how to fix it?

Error: The requested clipboard operation failed

Answer 1

I googled this question to see what I’d see, and a lot of people have asked this question, and none of them have gotten a solid answer…

So I went to the MSDN documentation and found a note that explains what most people who have asked this question describe… The symptom usually appears when the user switches to another application while the code is running. The note is quoted below, with the link to the documentation following:

All Windows-based applications share
the system Clipboard, so the contents
are subject to change when you switch
to another application.

An object must be serializable for it
to be put on the Clipboard. If you
pass a non-serializable object to a
Clipboard method, the method will fail
without throwing an exception. See
System.Runtime.Serialization for more
information on serialization. If your
target application requires a very
specific data format, the headers
added to the data in the serialization
process may prevent the application
from recognizing your data. To
preserve your data format, add your
data as a Byte array to a MemoryStream
and pass the MemoryStream to the
SetData method.

The Clipboard class can only be used
in threads set to single thread
apartment (STA) mode. To use this
class, ensure that your Main method is
marked with the STAThreadAttribute
attribute.

Special considerations may be
necessary when using the metafile
format with the Clipboard. Due to a
limitation in the current
implementation of the DataObject
class, the metafile format used by the
.NET Framework may not be recognized
by applications that use an older
metafile format. In this case, you
must interoperate with the Win32
Clipboard application programming
interfaces (APIs). For more
information, see article 323530,
"Metafiles on Clipboard Are Not
Visible to All Applications," in the
Microsoft Knowledge Base at
http://support.microsoft.com.

http://msdn.microsoft.com/en-us/library/system.windows.forms.clipboard.aspx

Funnily enough, this makes sense of a strange behavior I noticed in one of my own apps. I have an app that writes to an Excel spreadsheet (actually, to hundreds of them, modifying hundreds of cells each). I don’t use the clipboard at all, just the Interop API for excel, yet when it’s running, my clipboard clears every time a new spreadsheet is created. In my case, Excel is messing with the clipboard, even there is no discernible reason for it to do so. I’d chalk it up to one of those mysterious Windows phenomena that we mortals will never understand.

At any rate, thanks to your question, I think I understand my issue, so +1 to you for helping me out.