Hi:
We have been experiencing a weird problem since VS2010.
In some of our very large, multi project webform solutions, the VS UI was corrupting designer files by continuing to replace as an example - System.Web.UI.UpdatePanel with System.Web.UI.WebControls.UpdatePanel, same issue for scriptmanager etc. We could just touch the spacebar when editing the aspx files, and the designer would be corrupted with the above errors.
We are not the only persons having this issue, just google "System.Web.UI.WebControls.UpdatePanel" for other examples.
We moved up to VS2012, same issue. We just moved to VS2013, same issue - only on very large projects. We can create a new small web form project and have zero problems.
Other symptoms are drag and drop from the toolbox stops working, and viewing an aspx page in designer mode throws "HRESULT E_FAIL has been returned from a call to a COM component."
We have repaired VS2013, we have reinstalled VS2013, we have installed the VS2013 Update RC. No change.
Our development boxes are running Win7, with 4Gb ram, SQL 2012 with memory limited to .5Gb, and TFS 2013. The current VS2013 webforms is fully updated from NuGet, it will compile and run correctly, but we have to manually repair the designer files every time we touch the html.
Any thoughts? Memory issue?
TIA,
Bill