I have been successfully using my cookbook for a long time. However, suddenly the cookbook won't open. The screen says "Unable to locate the Cookbook: C:\Users\Public\DOCUME~1\MASTER~2\MYCOLL~\CookbookName.mc2.
This typically happens when the cookbook file on your computer becomes corrupt. That can happen for a variety of reasons unrelated to MasterCook. Generally a file becomes corrupt when a program is left running and that file is in use, and Windows crashes or restarts (automatic Windows Update). Generally any program that is left running and using a file is susceptible to corruption if the computer suddenly crashes or restarts.
If you have a backup copy of this cookbook, then you would want to use it instead. Please keep your files backed up on a regular basis. It is quick and easy. See MasterCook 15 Backup.
Otherwise, you can send us the corrupt file, and we can see if we can recover anything from it. Close MasterCook. Use Windows to go to this folder on your computer:
C:\Users\Public\Documents\MasterCook 15\My Collection
Open the C drive. Open the Users folder. Open the Public folder. Open the Public Documents folder. Open the MasterCook 15 folder. Open the My Collection folder. Find your .mc2 cookbook file within this folder and send it to us as an attachment to an email to firstname.lastname@example.org. We can confirm if it is corrupt and let you know. We will see if we are able to recover any recipes from it. Success ultimately depends on how badly damaged the file is.
Or, you could try to recover the recipes yourself. Download the free CB2CB program. Install and run it. Select MC2 as the Input format. Browse to your .mc2 file. Set MZ2 as the Output Format. Select Finish. After some time it will create an MZ2 file inside the same folder as your MC2 file. After it finishes being created double click on the MZ2 file. MasterCook will ask you where to import those recipes. Create a new cookbook in this window. Import those recipes into that new cookbook.