Changing website framework: Any negative SEO ramifications?

[BBEXNinja]

Hello! We have a website that is built using Asp.net. My colleague and I are wondering whether or not changing the framework from Asp.net to php or html would have any negative impact on current rankings.

My colleague was told by an SEO company that doing this would have a big negative effect, but we just can't see why that would be. The URLs of the site do not have an .asp extension, so we don't feel there would be any issues with 404s after the migration. The content, meta data and URL structure would remain the same.

We posted this question in the Webmaster Central Forum and were told by a top contributor that it wouldn't have any negative impact, but we wanted a second opinion here. Thanks!

[Hutch42]

There should be no issue as long as you do everything that you have planned.

[justin-brock]

I think Hutch42 is right. If your urls have no file extensions on them (.asp, .php, .htm), you really shouldn't see any dip from merely changing over.

It would be worth triple-checking about the extensions, though. We changed our site over a few years back and saw a dip in some key lead-generating pages that had extensions on them.

One place you may see a difference is with load times. Your pages' code structure will likely change. And .NET/IIS sometimes has different speeds than a LAMP stack even with the same content.