Fatal error: Call to undefined function wp_is_mobile() in /home/content/15/77955

Which is / where do I find my “current theme”?
How do I change it?

See screen shot from Godaddy

So you are already using the twenty eleven theme? Then scratch my suggestion above.

Hmmm… Try downloading a fresh copy of wordpress 3.4. Extract it to your desktop. Replace the entire contents of the wp-admin and the wp-includes directories. DO NOT mess with the wp-content directory.

Also, you might want to try to rename your plugins folder. Navigate to wp-content and change the plugins folder to something like plugins-temp. This will disable all your plugins, in case it’s a plugin conflict.

Try both of these and let me know.

@josh
– I very much appreciate your help. All of this reads like gobbledygook to me.

So you are already using the twenty eleven theme? Then scratch my suggestion above.
– If you say I am, then I am. I wouldn’t know.

Hmmm… Try downloading a fresh copy of wordpress 3.4. Extract it to your desktop.
-Downloaded
– Extracted
– On Desktop

Replace the entire contents of the wp-admin and the wp-includes directories. DO NOT mess with the wp-content directory.
– Don’t know how to do this. Can it be done in my GoDaddy account?

Also, you might want to try to rename your plugins folder. Navigate to wp-content and change the plugins folder to something like plugins-temp. This will disable all your plugins, in case it’s a plugin conflict.
– Tried this on the phone with GoDaddy and it did not work.

Try both of these and let me know.

You can do it via GoDaddy.

Browse to your root directory, and you should see the following three folders (among others), wp-content, wp-admin, wp-includes.

Delete the wp-admin and the wp-includes and upload the new ones from your desktop.

Leave the wp-content directory alone.

Browse to your root directory, and you should see the following three folders (among others), wp-content, wp-admin, wp-includes.
Delete the wp-admin and the wp-includes
Leave the wp-content directory alone.
– Done

and upload the new ones from your desktop.
– How do I do this?

When I get “Destination Selected: html” I “choose file” and a window opens. I click to my desktop, I click to “wp-admin” and I get this:

Click for screenshot

Like I said, I really don’t know what I am doing so I apologize for need a step by step here but that really is what I need.

Thank you.

And for the record, this is what my site looks like now

Click for Screenshot

I’m not sure how the CPanel with GoDaddy works. I’ve never used it before.

You should have the option to upload files from your computer. You want to upload those two folders into the same directory holding the wp-content folder.

You may need to call GoDaddy for the specifics on “how-to”.

Called GoDaddy. They helped me. Did not work. Now getting this when I try to login:

Fatal error: Class ‘WP_Theme’ not found in /home/content/b/u/r/burgerconquest/html/wp-includes/theme.php on line 106

Was having the same error BurgerConquest. This thread helped https://www.ads-software.com/support/topic/upgrade-to-34-from-311-fatal-error?replies=8#post-2934061
Replace the wp-settings.php file and that worked for me, but must say that all of Josh’s advice helped get me to the point where this worked.

Thank you Josh! Much appreciated.

My pleasure Lee.

@burgerconquest,
Let us know how Lee’s solution works for you.

BurgerQuest,

Very frustrating, I know. I went through all of the above and nothing. But, I was able to finally get into my dashboard by going in with https://yoururl.com/wp-admin/post-new.php, I think I got lucky. But once I got into there I was able to open some of the commands, like install themes and at the top of the page it said update failed to fully install click here to re-upload and when I did it all stared working again. Like I said, I might have just gotten lucky but you can give it a try. Good luck! Thanks Everyone for your help!

Thanks all. Still in the process

After deleting the wp-admin and the wp-includes, then downloading an new wordpress 3.4 & re-uploading & it not working, I called GoDaddy.

They suggested I create a new folder for my wp-content and then copy the content over. From there, they wanted me to try a totally brand new upload.

According to my screen, my content is still copying and it’s been 13 hours with no end in sight. Very frustrated. Until this is done, I am not doing anything else for fear of losing the site entirely.

If anyone else has a better suggestion, I’ll gladly take it. If you live in NYC and help me, I’ll gladly buy you some drinks at the bar I own.

Thanks

i found the answer here

https://www.ads-software.com/support/topic/upgrade-to-34-from-311-fatal-error?replies=13

doing the wp-settings.php fixed it for me

Solution of Fatal error: Call to undefined function wp_is_mobile():

You need to rename your file wp-admin and re upload the folder wp-admin file from you fresh code that’s all

??

Rename the wp-admin in my root directory? What do you mean when you say upload folder from fresh code?? Thanks!