Solution for "illegal characters in path" error message in ASP.NET

[Steve Grahovac]

I have been having trouble the last few days opening any ASP.NET web
forms in the design view in the designer. Every time I clicked on an
aspx file I got a message box with the error "Unable to open in
designer. Illegal characters in path" and the file is instead opened
in HTML view. I don't know what application or situation may have
caused this error. I looked on the newsgroups and noticed that
numerous other people were having this problem.

The way I fixed it was to:
1> Go to another machine with same version of VS.NET and OS
2> run "regedit"
3> Select "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework" branch
from tree on the machine that does not have this issue.
4> Select File->Export from the menu of Registry Editor to export
branch to file.
5> Double-click on this file on the machine that is having the issue.

The error message should be gone and the aspx files should now be
viewed correctly in the designer. This is what worked for me.

I hope this helps other people who have struggled with the same issue.

 

[Jim Cheshire [MSFT]]

Steve,

Thank you for posting this to the group!

Jim Cheshire, MCSE, MCSD [MSFT]
Microsoft Developer Support
ASP.NET
(e-mail address removed)

This post is provided as-is with no warranties and confers no rights.

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