All my server-controls became unrecognized!!! like there's compilation error or web.config missing! (in website)

Question

User82281683 posted

hi!

please help - the problem is in post subject.

I have lots of warnings with following text:

"Warning 10 Element 'HyperLink' is not a known element. This can occur if there is a compilation error in the Web site, or the web.config file is missing. C:\Users\Pavel\Documents\Visual Studio 2010\WebSites\BioWebSite\ToScientist.aspx 26 18 C:\...\BioWebSite\" 

But web.confg is there! And there's no compilation error!

Site builds just fine. And If I upload it to my hoster - it works!

 

But with all these errors I cant add controls to pages - VS2010 adds hyperlink without ID, and intelisens stoped to work.

Strange, but in my other project (web-application) I have no such difficuty.

Answer 1

User578079708 posted

1. Clean the solution
2. Rebuild the solution

have a try.

Answer 2

User82281683 posted

what do you mean "clean"?

 

I did rebuild.

I dd reset VS settings to default (it helped in beta).

Nothing wored yet 

Answer 3

User1759134392 posted

hi Vorlosha,

Sorry that you are running into this error with VS 2010. If possible, can you send me a zip file of your project to : balach AT microsoft DOT com, and I can help investigate the cause of that error?

Thanks,
Bala Chirtsabesan | Visual Web Developer Team

 

Answer 4

User1759134392 posted

hi Vorlosha,

Thanks for sending me your project. Good to know that your issue is solved after trying the workaround below - I'm posting the workaround here for benefit of others who might run into this:

As a workaround, you can try the following: 

Close VS, delete schema cache, and re-open VS. You can find the schemas under something like:

C:\Users\Pavel\AppData\Roaming\Microsoft\VisualStudio\10.0\ReflectedSchemas

 

It is safe to delete all files in this folder.

Bala Chirtsabesan
Tester, Visual Web Developer Team

 

Answer 5

User1424338504 posted

I had the same problem and tried this suggestion. Works like a charm.

Thanks for the tip.

Srini

Answer 6

User-849224665 posted

Dear Chirtsabesan, thanks a lot  for your helpful comment.

The mentioned path works for Windows 7 users but the path for Win Xp is:

C:\Documents and Settings\[your username]\Application Data\Microsoft\VisualStudio\10.0\ReflectedSchemas

 

hope this helps,

Matin Habibi

 

Answer 7

User-849224665 posted

Dear Chirtsabesan, thanks a lot  for your helpful comment.

The mentioned path works for Windows 7 users but the path for Win Xp is:

C:\Documents and Settings\[your username]\Application Data\Microsoft\VisualStudio\10.0\ReflectedSchemas

 

hope this helps,

Matin Habibi

 

Answer 8

User-1248370775 posted

hi

i had the same problem

i changed the 

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>

to

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajax" %>

 

and the intellisence is back again

 

Answer 9

User-1530816057 posted

Hello,

I have the same problem with the UserControls registered in my content page. I tried this solution

Close VS, delete schema cache, and re-open VS. You can find the schemas under something like:

C:\Users\Pavel\AppData\Roaming\Microsoft\VisualStudio\10.0\ReflectedSchemas

but still I have that weird warning. It is weird because it doesn't alert every control, but one or two (randomly!!).

I can put two of them without troubles; I get the annoying warning adding another one.

No compile errors; correct registration as for the other controls.

What's the problem? is it possible that the installation of VWD 2010 express got broken?

Answer 10

User706013099 posted

A previously working installation of VS 2010 Professional has today suddenly started behaving oddly in a similar manner to that described. I first noticed that intellisense was not working and then saw that all controls (whether ASP.NET or Ajax Toolkit) were showing in the Properties Pane as HTML ELEMENT. The only ones that are not are my own custom controls. But the website still builds and runs OK. I tried your suggestion, which initially seemed to work but then the problem came back within a few seconds. It seems like my installation is broken - any other ideas? Incidentally, there was an ExtensionManager update today - could that have caused it? Is there any way to restore all VS settings?

 

Jon

Answer 11

User-670052939 posted

I had the following problems in VS 2013 express:

1. <asp:....  underlined and showing an error, something like 'unrecognized tag prefix', since gone because I have fixed it
2. Properties not showing for ASP controls, but showing fine for HTML controls
3. No smart tags.

I tried the following:

1. Fixing the installation using control panel -> MSVSE2013 -> change -> Mend (or something like that anyway.) - Did not fix.
2. Removing Nuget Ajax Control Toolkit (I wasnt using any of it in my project) - Did not fix
3. Build, Rebuild, Clean - Did not fix
4. Deleting / renameing my local Documents-> Visual Studio 2013 folder (VS creates a new fresh one.) - Did not fix
5. Fiddling with the web.config file as suggested on other forums (can't remember the details sorry) - Did not fix

I fixed it by:

1. Creating a brand new project
2. Adding a new button control (everything started working fine at this point.)
3. Quite VS
4. Restart VS and reload my project - suddenly everything was OK again!

Hope this helps someone.

Answer 12

User-445056098 posted

Thanks it was a correct solution