How do I Unignore a file in TortoiseSVN?
Solution 1:
Just edit the svn:ignore property (in the subversion tab of the directory properties). (If you ignored a subfolder, select the property tab of it's parent folder)
Solution 2:
If you right click on the directory containing the file and select SVN Properties, you should see an svn:ignore property with a list of ignored files. Simply edit that list and remove the rule ignoring your file.