I found the answer searching through the earlier discussions,
I implemented this remedy and it fixed my issue, here it is:
".. open start menu > Run > type "regedit" into box > Enter > navigate through HKEY_CURRENT_USER > software > Adobe > Acrobat Reader > 9.0 > Window > cAVLoupe. Open this folder. (If using Vista, open all programs > accessories > Run > enter "regedit" > enter and then as above). You will get a screen with registry entries including ibottom, ileft, iright and itop. Some of these will have large numbers attached and this is the problem. Right click on these 4 icons in turn and left click modify. Then tick the decimal option and replace the large numbers with"0" in the box for each entry. You may find that the pan tool now stops working! If so, repeat the process but instead of cAVloupe, go into cAVNavigator instead, and change the large numbers only.."