I have lost most of my Library Path in Delphi XE after upgrading from Delphi 2010,
Now even some simple app will fail to compile.
Is there any way to recover
Do you still have your Delphi 2010 install around? You could just copy the library path from there.
For me this happened after installing VirtualTreeview 4.8.7 (? 5?) in Delphi XE under win7X64. I tried the delete reg path above (after saving it off to a file) and no go.
Then I noted that there was a dropdown in the library path that remembered previous changes to the whole path. Set it (and all the other remembered ones) back a step or two and everything compiled.
Sooo, then I reimported the originally bad one watching for differences. Right there in the topmost line
$(BDSLIB)\$(Platform)\release was $(Platform)\release (in the incorrect version)
Modified to have the full line in and all is well. $(BDSLIB)\$(Platform)\release
I expect this is because the installer strips these out and rebuilds them, but treats this as two lines instead of one.
Scotto the Unwise (spellcheck for the win)
I think there's none, if they aren't saved accidentally somewhere on your hard drive. But the safe way is to make a clean reinstall of Delphi, then reinstall all the components.