'Mail quit unexpectedly' How do I fix this in Mavericks?

Question

Hi,
I recently upgraded to Mavericks. Mail has been working fine for the last few weeks. Yesterday I was fooling around with a third party app called PresentYourApps which can hide the dock and menu bar for specific apps you have open.
I stupidly asked it to 'Remove Menu Bar and Dock' for my Mail program. Since then Mail will not open at all. I get the 'Mail quit unexpectedly' message. I have tried to find an option to undo the mess I've made within PresentYourApps but I can't find one. I'm pretty sure now that the software was not compatible with Mavericks.
I've pasted the full error report I get from Mail below. I am not a computer whizz so I've no idea what this means. I probably deserve this pain for being so stupid  but I really need Mail for work so I'd really appreciate it if someone can help... please help!
Process:         Mail [5909]
Path:            /Applications/Mail.app/Contents/MacOS/Mail
Identifier:      com.apple.mail
Version:         ???
Build Info:      Mail-1816000000000000~1
Code Type:       X86-64 (Native)
Parent Process:  launchd [189]
Responsible:     Mail [5909]
User ID:         501
Date/Time:       2013-10-31 09:50:53.418 +0000
OS Version:      Mac OS X 10.9 (13A603)
Report Version:  11
Anonymous UUID:  CCAA7CDD-3BED-82CE-356F-F7E7271E2C3C
Sleep/Wake UUID: FF4EA689-6C95-4EDD-8B57-5F46F4157160
Crashed Thread:  0
Exception Type:  EXC_CRASH (Code Signature Invalid)
Exception Codes: 0x0000000000000000, 0x0000000000000000
VM Regions Near 0x7fff740530a8 (cr2):
    __LINKEDIT             00007fff6263b000-00007fff6264f000 [   80K] r--/rwx SM=COW  /usr/lib/dyld
--> Submap                 00007fff70000000-00007fff80000000 [256.0M] r--/rwx SM=PRV  process-only VM submap
    unused shlib __DATA    00007fff72327000-00007fff74b2f000 [ 40.0M] rw-/rw- SM=COW  system shared lib __DATA not used by this process
Thread 0 Crashed:
0   dyld                                    0x00007fff625c9028 _dyld_start + 0
Thread 0 crashed with X86 Thread State (64-bit):
  rax: 0x000000000000000d  rbx: 0x0000000000000000  rcx: 0x0000000000000000  rdx: 0x0000000000000000
  rdi: 0x0000000000000000  rsi: 0x0000000000000000  rbp: 0x0000000000000000  rsp: 0x00007fff55739d58
   r8: 0x0000000000000000   r9: 0x0000000000000000  r10: 0x0000000000000000  r11: 0x0000000000000000
  r12: 0x0000000000000000  r13: 0x0000000000000000  r14: 0x0000000000000000  r15: 0x0000000000000000
  rip: 0x00007fff625c9028  rfl: 0x0000000000000201  cr2: 0x00007fff740530a8
Logical CPU:     0
Error Code:      0x020000f4
Trap Number:     133
Binary Images:
    0x7fff625c8000 -     0x7fff625fb817  dyld (???) <D1DFCF3F-0B0C-332A-BCC0-87A851B570FF> /usr/lib/dyld
External Modification Summary:
  Calls made by other processes targeting this process:
    task_for_pid: 0
    thread_create: 0
    thread_set_state: 0
  Calls made by this process:
    task_for_pid: 0
    thread_create: 0
    thread_set_state: 0
  Calls made by all processes on this machine:
    task_for_pid: 1561
    thread_create: 7
    thread_set_state: 0
VM Region Summary:
ReadOnly portion of Libraries: Total=288K resident=280K(97%) swapped_out_or_unallocated=8K(3%)
Writable regions: Total=8448K written=0K(0%) resident=12K(0%) swapped_out=0K(0%) unallocated=8436K(100%)
REGION TYPE                      VIRTUAL
===========                      =======
STACK GUARD                        56.0M
Stack                              8192K
VM_ALLOCATE                           8K
VM_ALLOCATE (reserved)                8K        reserved VM address space (unallocated)
__DATA                              252K
__LINKEDIT                           80K
__TEXT                              208K
mapped file                        4016K
shared memory                         4K
===========                      =======
TOTAL                              68.5M
TOTAL, minus reserved VM space     68.5M

Answer 1

Rodrigohola,
Navigate to /Users/YOUR NAME/Library/Application Support/PresentYourApps in Finder.
In the PresentYourApps Folder inside the Application Support folder, there should be another folder called Mail. Inside that folder you’ll find all the backuped files. Info.plist should be one of them. This file is the one PresentYourApps changes. Before you do anything else, please make another copy of that file somewhere safe.
After you’ve made a backup copy, please proceed as follows:
Navigate to /Applications in Finder and right-click (control-click) onto Mail and select “Show Package Contents”. A new finder window appears. select Contents. Replace the Info.plist file in that Contents folder with the backuped one from the Application Support folder.
Try launching Mail again.