Space backup does not progress

[Shubha]

We migrated a Confluence server running on Linux to a Windows machine. The XML restore did not work, so we imported each space in to the new server. Now, in the new Confluence, i cannot take an export of any of the spaces. I tried both the older spaces that were imported as well as creating a new space with just one page. 

The page just shows no progress,  

Any help is appreciated.

[AnnWorley]

I am assuming the space exports are to XML, not HTML or PDF. Please see XML Backups and Space Export/Import Troubleshooting

Since you mention that a newly created space also hangs during export, I tend to suspect Out of Memory errors. Please search for "outofmemory" in the logs at <confluence_install>/logs/ (anything recent in this directory) and <confluence_home>/logs/atlassian-confluence.log
Note: The <confluence_home> directory is the path defined in the following file: <confluence_install>/confluence/WEB-INF/classes/confluence-init.properties

In the atlassian-confluence.log there should be entries for the export starting and finishing - look for the phrase "long running task" to see if there is any explanation for the export failing, or whether the export is still running but just not updating the UI.