Problem with extensions and PHP

Very new to this...hope you can help...

I downloaded and installed 4 date and number format extentions using extension manager and that went fine...

FX_PHP_DateTFormats.mpx

FX_PHP_NumFormats.mpx

MX218277_PHP_formatdate.mxp

MX744392_PHPServerFormats.mpx

I tried to appy formats to my data and and it just seamed to trash everything in the file.

I then uninstalled the extensions figuring there was conflict between extensions. Now i cannot reinstall any of them.

the error message from extension manager  is "cannot update menus"

How do I get back to a healthy starting positon to re try?