File Checkout Issue

1) SharePoint 2007 have issues that files are locked out continuously and not able to edit/discard check out. A) clear the IE cache & local machine temp files. If the issue persist then ask the user to check in the file. Keep the version of list/library to maximum 10 numbers. If the issue still persist then save as file for local then change the file name & upload. Do the file edit. or Open a new file--> select open --> enter the url of the file & then do the changes