Gotcha for the day.
When you try to customize a list in either InfoPath designer/ SharePoint designer 2010 from the web browser. If it doesn’t open, its probably because the IE is running in 64 bit mode.
The solution was to open the site through IE 32 bit. On opening it, made sure the Control Panel ->Admin Tools->Services->Web Client is started and the properties is set to ‘automatic’ instead of manual.
Even then it didn’t start on clicking ‘Edit in SharePoint designer’, but once I opened the SP designer and then clicked the link, it opened the site/page in the designer mode.
Another tid bit: Chrome/Firefox/IE64 doesn’t seem to launch the designer for edition.
If this doesn’t resolve the issue which it didn’t in another situation for me, check out what I did that helped.
I went to check if Sharepoint OpenDocuments Class add on was enabled in IE and saw that it wasn’t even in the list. I did have SharepointOpenXMLDocuments enabled though.
These are the steps that help with the resolution.
1.Repaired Microsoft Office install. (Control Panel->Programs & Feautres->MS Office(change) and then choose repair.
2.Restarted the machine.
IE->Manage Add-Ons->SharePoint OpenDocuments Class was now available and enabled.
Opened the SP list and clicked ‘Customize Form’ and it opened it with InfoPath designer.
Trust this helps someone.