Magento not responding after category save

[sts2f]

I just changed the sorting of some products in a category and after saving it I noticed that Magento no longer drops down any tabs like sales or system. The only tab link I can click on is dashboard. I can't get to cache or anything. Please help! Thanks!

[sts2f]

Could this be due to an extension?

[JLHC]

It can be due to a few reasons, including file permissions, JavaScript and yes extensions as well. 

Did you install any new extensions recently? Have you tried this with another web browser and make sure JavaScript is not disabled? 

[Mike Hall]

his is because when you save category then it also run indexes.So if you have enabled flat category,then set the indexing mode "Category Flat Data" to manual and then save.