Microsoft LightSwitch RTM which became available for public download, a 90 day evaluation copy presented an unusual installation problem. It took over a day and half of working on it and finally was solved.
The problem:
This may not happen on all computers but may happen on some in both x32 as well as x64 bit architectures. The typical message one would get is that the installation will not proceed unless an existing Beta 1 is removed as shown in the next image.
This sounds an unreasonable message as the Beta 1 is removed from these computers; there is no indication of a Beta 1 in the
Control Panel | Programs and Features (Windows 7); and no trace of a 'LightSwitch' component in the Registry.
Most of the reported cases, perhaps came from users who had installed Beta 1 some time or another in the past and who had removed it to accommodate Beta2 (which could not be installed if Beta 1 were present). It was a kind of given that if Beta 2 was on a machine, Beta 1 could not have been present. One user who never had Beta 1 just removed Beta 2 and it worked without any problem.
The Solution:
Finally Robert Schoen, a Microsoft Employee suggested among other suggestions to remove the following two keys in the Registry (refer to associated command,
Regedit). For details follow this link,
http://social.msdn.microsoft.com/Forums/en-US/lightswitch/thread/d976ac44-8b90-464b-b50d-e110868e7bb5/
ON x64 machines go to:
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\DevDiv\VS\Servicing\10.0\STD and remove this STD key (this will be for Beta1)
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\DevDiv\VS\Servicing\10.0\vslscore and remove this vslscore key (this will be for Beta2)
On x86 machines go to:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DevDiv\VS\Servicing\10.0\STD and remove this STD key (this will be for Beta1)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DevDiv\VS\Servicing\10.0\vslscore and remove this vslscore key (this will be for Beta2)
This is the one that worked for me, and later many others reported success on both architectures. After deleting these keys, the installation went very smoothly as in the following screen shots.
Compared to Beta 2 only three components seen in the screen shots were downloaded and installed.